Introduction

Hi! I am Daniel Lim Jhao Jian. Since the inception of this blog in June 2009, I have been sharing a lot of my experience, knowledge and ideas here. I hope you will find this blog useful. Thank you for visiting my blog.

Saturday, 20 December 2014

Simple decision, great consequences

Now, I am studying Medicine at Newcastle University Medicine Malaysia (NUMed) under sponsorship of the JPA scholarship. Actually, it was an important decision I made in the past which enabled me to get the JPA scholarship.

Back in secondary school, I took 10 subjects for my SPM examination. I chose Information and Communication Technology (ICT) as my 10th subject because it is a Science subject which is studied in English. However, many other students in my school chose Prinsip Perakaunan as their 10th subject. In the beginning, ICT seemed to be an easy subject. The almost complete SPM ICT reference book has less than 100 pages, and its size is smaller than other SPM reference books. Therefore, we did not have to study a lot for ICT. The exam questions also looked quite easy. 

However, all ICT students in my school were shocked when the SPM 2010 results were released in March 2011, because no one in our school got A+ for ICT, and only a few students got A or A-. Worst of all, we later heard the news that no student in the whole Malaysia got A+ for ICT in SPM 2010. Many ICT students including me were worried about that. As a result, many students dropped ICT after Form 4. 

Despite that, I did not consider dropping ICT. Since ICT is a subject where we can make full preparation for it, I was confident that as long as I fully understood it I would be able to get A+ in SPM. A few of my friends advised me to drop ICT. They said that it was very risky for me to take ICT since my target was to get 10A+ in SPM. I did not listen to their advice and I insisted on taking ICT in SPM.

In the end, I successfully got A+ for ICT in SPM. Instead, out of my expectation I did not get A+ for English. Overall, I got 9A+ and 1A for my SPM. With that, I could get the MOE Bursary which sponsored for my A Level, since the requirement to get the MOE Bursary is 9A+ or above in SPM. Since I was a Bursary student, I was automatically offered the JPA scholarship after I completed A Level and met the requirements. 

Looking back, if I dropped ICT back then, things would be completely different now. Without ICT, I would only have 9 subjects in SPM and my results would be 8A+ and 1A, which would not qualify me for the MOE Bursary. Consequently, I would have to apply for the JPA scholarship as a non-Bursary student, which would require me to go through interviews and there is no guarantee of getting it. Since my interview skills is not very good, it is very likely that I would not get the JPA scholarship.

Sometimes, a simple decision which seems to be very small can actually have a great effect on your life. So, always think carefully before making a decision. When you have decided on something, just go for it and don't let others influence you, because only you know what is best for yourself.

Hope everyone will learn something from my story. Thanks for reading this.

Thursday, 20 November 2014

My A2 Level Examination

I sat for the A2 Level examination in the May 2014. A2 Level is the second half of A Level. I studied A Level at Taylor's College Subang Jaya. The A2 Level examination contributes half of the marks for the overall A Level results. The other half comes from the AS Level examination which I took in October 2013. I took 4 subjects for A Level, which were Biology, Chemistry, Mathematics and Physics. My A2 Level examination was from 9 May 2014 to 22 May 2014.

This is my diary during the A2 Level examination.

2 May 2014 (Friday):
This was my last day of normal college before the A2 Level examination started. After college, I had lunch with my friends at Ha Ha Pan Mee Shop. After returning home, I did revision for the examination.

3 May 2014 (Saturday) to 7 May 2014 (Wednesday):
There were no college during the 5 days. I spent most of my time doing revision for Biology Paper 4 and Chemistry Paper 4. I did past year questions for Biology Paper 4 and Chemistry Paper 4. I also revised my teacher's notes and the notes that I took down myself while in class.

8 May 2014 (Thursday):
I went to college on that day because my Biology teacher held an extra class for Biology Paper 5. The extra class was in the afternoon but I went to college in the morning. Before the extra class started, I went to the learning hub of my college and did revision for Biology Paper 5. Later, I met a few of my friends. I had lunch with them at Good Friends Cafe before going for the extra class. After the extra class ended, I continued revising Biology Paper 5 at home. I went through the past year questions and the mark schemes on the internet. I also revised the Practical worksheets, my teacher's notes and the textbook.

9 May 2014 (Friday):
It was the first day of my A2 Level examination. The subject tested on that day was Biology Paper 5. The questions were extremely difficult, much more difficult than what I had expected. The style of the questions was very different compared to the questions in the past few years. For the question on planning experiment, it was about genetic fingerprinting, which I did not revise much before the test. I could not answer many of the questions. I was not at all confident of this paper and I estimated that I would score only about 10/30. Many of my friends also felt that the paper was very difficult. After returning home, I revised Biology Paper 4 and Chemistry Paper 4.

10 May 2014 (Saturday) and 11 May 2014 (Sunday):
There were no examination during the 2 days. I spent most of my time doing revision for Chemistry Paper 4. I revised my teacher's notes.

12 May 2014 (Monday):
The subject tested on that day was Chemistry Paper 4. The questions were not difficult and were easier than what I had expected. However, there were a few questions that were a bit difficult and I did not answer them well. I also made a few careless mistakes. I was confident of scoring above 80/100 for this paper. After returning home, I revised Biology Paper 4. I did not revise for Mathematics Paper 4 although it was also tested on the next day because I did not have enough time.

13 May 2014 (Tuesday):
Mathematics Paper 4 and Biology Paper 4 were tested on that day. Mathematics Paper 4 started first in the morning followed by Biology Paper 4 in the afternoon. For Mathematics Paper 4, the questions were moderately difficult. However, I made careless mistakes in a few questions. Also, there was a question which stated that I had to solve it using energy method, but I solved it by calculating the acceleration and then using F=ma because I did not read the question carefully. Therefore, I was confident of scoring only about 40/50 for this paper. For Biology Paper 4, many of the questions were extremely difficult, just like Biology Paper 5. Most questions tested on application instead of just knowledge and understanding. There were several questions that tested on the topic of Gene Technology which was the topic I disliked most. I did not revise much for that topic because I thought that not many questions would test on it since Biology Paper 5 already tested on that topic. So, I could not answer many of those questions. I also did not have enough time to finish all questions and I had to leave some questions blank. Therefore, I screwed up this paper. Since both Biology Paper 4 and Paper 5 were very difficult, I was not at all confident of getting A* and I was confident but not 100% confident of getting A. I was quite worried of Biology.  Many of my friends were also quite worried. That day was my most stressful day throughout my A2 Level examination.

14 May 2014 (Wednesday) to 18 May 2014 (Sunday):
There were no examination during the 5 days. On 14 May, I spent most of my time relaxing and I studied very little. Then from 15 May to 18 May, I did revision for Physics Paper 4. I did past year questions for Physics Paper 4. I also revised my teacher's notes.

19 May 2014 (Monday):
Physics Paper 4 was the subject tested on that day. The questions were a bit difficult, but were easier than what I had expected. There were a few questions that I could not answer. I was confident of scoring above 70/100 for this paper. After returning home, I revised Mathematics Paper 3. I did past year questions for Mathematics Paper 3. I also went through the examples in my teacher's notes.

20 May 2014 (Tuesday):
The subject tested on that day was Mathematics Paper 3. The questions were quite easy. I could finish all the questions within the time limit and I even had time to recheck all my answers. I was confident of scoring very high marks and maybe full marks for this paper. I was very sure of getting A* for Mathematics. After the test, there was a briefing in my college for all students who were sponsored by the MOE Bursary and I attended it. The briefing lasted for 1 hour and they told us the steps that we had to do in order to be sponsored by the JPA scholarship. My friends waited for me outside the venue of briefing until the briefing was over. After that, I had lunch with my friends at a Korean restaurant near my college. After returning home, I revised Chemistry Paper 5. I went through the past year papers and the mark schemes on the internet.

21 May 2014 (Wednesday):
Chemistry Paper 5 was the subject tested on that day. The questions were a bit difficult. There were a few questions that I did not answer well. I was confident of scoring above 15/30 for this paper. I was very sure of getting A* for Chemistry. After returning home, I revised Physics Paper 5. I went through the past year papers and the mark schemes on the internet. I also did some past year questions for Physics Paper 5.

22 May 2014 (Thursday):
It was the last day of my A2 Level examination. The subject tested on that day was Physics Paper 5. The questions were quite easy. I was confident of scoring above 25/30 for this paper. I was very sure of getting A* for Physics. After the test, I went to Sunway Pyramid with my friends. There, we watched X-Men: Days of Future Past and then had dinner at Bubba Gump Restaurant. After that, I returned home. Even though the A2 Level examination was over, I still could not relax because I had to prepare for my IMU interview on 29 May 2014 and write my personal statement for my application to NUMed Malaysia.

In my opinion, this is the ranking of all papers from the most difficult to the easiest:
1. Biology Paper 5
2. Biology Paper 4
3. Physics Paper 4
4. Chemistry Paper 5
5. Mathematics Paper 4
6. Chemistry Paper 4
7. Physics Paper 5
8. Mathematics Paper 3

My A Level results was out on 12 August 2014 at 1PM. A few days before the results was released, I felt worried about my results. I was very confident of getting A* for Physics, Chemistry and Mathematics, but I was not 100% confident of getting A for Biology. The conditions of my offer from NUMed Malaysia was AAA including Chemistry and Biology. So, if I did not get A in Biology, my offer from NUMed Malaysia would be withdrawn. If that happened, I could still study Medicine at IMU and be sponsored by the JPA scholarship, but it would be very disappointing for me. At that time, my greatest hope was that I could get A for all subjects including Biology, and I was willing to give up my A* in exchange for that.

On 12 August 2014, just before the results was released, I was very nervous. I was at my house in Subang Jaya at that time. In order to make myself feel less nervous, I kept playing the song 是我在做多情种 at high volume using my iPad. It is a very nice song, and I knew the song just a few days before that. At 1PM, I checked my results at the Cambridge International Examinations website using the username and password provided by my college. I was so happy to know that I got A* for all 4 subjects including Biology. I could not control myself and I shouted 'Yes!', even though there was no one in my house at that time. I then informed my grandparents and parents about my results and they were very happy about that.

However, on that day after I got my results and on the following day, my body did not feel well, maybe because I was too stressed before that. I sent my A Level results to both NUMed Malaysia and IMU. Both universities then converted my conditional offer to unconditional offer. I also submitted my A Level results to JPA. On 29 August 2014, my A Level Statement of Results was out and I went to my college to collect it. 

This is my A Level results:
Biology: A* (92%)
Chemistry: A* (93%)
Mathematics: A* (94%)
Physics: A* (95%)

The interesting thing about my results is that my percentage uniform marks for the 4 subjects are in an ascending order.

If you find this story interesting, you may want to read this too:
http://daniellimjj.blogspot.com/2014/01/my-2013-year-end-examination.html 

Sunday, 19 October 2014

The process of my application to universities

I obtained 4A* for A Level and AS Level and 9A+ 1A for SPM. Some people may think that with such academic results, I will have no problems in my application to universities. However, in reality the process of my application to universities had not been smooth and easy. In fact, I had to go through several challenges and disappointments in my application to universities. Here, I am sharing the entire process of my application to universities.

On 29 July 2013, I started applying to UK universities through UCAS. I chose University of Cambridge, University College London (UCL), Imperial College London (ICL) and King's College London (KCL) for Medicine course. I was required to write a personal statement for the application, which I felt was a difficult task. Therefore, I delayed submitting the application. Later, the deadline of the application to Cambridge which was 12 August 2013 had passed, so I chose to apply to University of Oxford instead of University of Cambridge. The deadline of the UCAS application for Medicine course was on 17 September 2013. I started writing my personal statement just a few days before the deadline. I finished writing the personal statement on time, but I had no time to have it checked by anyone. To me, my personal statement seemed to be quite satisfactory. I submitted the UCAS application on 17 September 2013 itself. 

Oxford, UCL and ICL required me to take the BMAT test while KCL required me to take the UKCAT test. I was only able to sit for BMAT but not UKCAT, because the deadline had already passed when I tried to book a test centre for UKCAT. On 3 October 2013, I attended a mock interview for Oxford which was arranged by Taylor's College. I was quite nervous before the interview since this was the first time I attended an interview. The interview was quite difficult, but it was still easier than what I had expected. I thought that I performed quite well during the interview since I could answer most of the questions. However, the interviewer's remark on me was that I was an "unfortunate interviewee with poor communication skills" and he gave me grade C+ for the mock interview. I was a little disappointed but not too disappointed since grade C+ is actually still a pass.

On 3 December 2013, I was rejected by Oxford without being shortlisted for an actual interview. Oxford said that it was because the application to Oxford was too competitive. I did not feel too disappointed, as I was confident that I would be shortlisted for interview by at least one other UK university. Later that month, I also started my application to University of Hong Kong (HKU). Again, I was required to write a personal statement. I decided to just use the same personal statement that I used for my UCAS application earlier and make some minor changes to it. I submitted the application to HKU on 21 December 2013. At that time, I still did not have my actual A Level results so I had to use my forecast results to apply to universities.

In January 2014, I was first rejected by UCL, followed by ICL and then KCL. All of them did not shortlist me for interview. That made me feel very disappointed. Since I was rejected by all UK universities, I was allowed to apply to another UK university through UCAS Extra. However, for Medicine course very few universities were still open for application, and all those that were still open required the UKCAT test which I did not take. In other words, I had no more chance to study Medicine in UK. On 17 February 2014, I submitted my application to National University of Singapore (NUS). Actually, NUS did not accept forecast results for application to Medicine. However, I still applied to NUS, hoping that they might give me an offer for deferred entry in 2015. Later, I found out that NUS would not give offers for deferred entry. So, I did not pay the application fee. My application was automatically withdrawn after the payment deadline on 28 February 2014.

At that time, many Malaysian private universities were open for application. Initially, I planned to apply to International Medical University (IMU), AIMST University, Monash University Malaysia, Newcastle University Medicine (NUMed) Malaysia, Perdana University, UCSI University, Cyberjaya University College of Medical Sciences (CUCMS) and University Kuala Lumpur - Royal College of Medicine Perak (UniKL-RCMP), because all of them are in the list for JPA scholarship. I later realised that AIMST, CUCMS, UniKL-RCMP, UCSI and Monash Malaysia do not accept forecast results. I had to wait until my actual results is released in August 2014 before I could apply to those universities, but by then they are likely to be almost full except for Monash Malaysia where the intake is in March 2015.

Therefore, I could only apply to IMU, NUMed Malaysia and Perdana. I submitted the application for IMU on 21 February 2014. However, NUMed Malaysia required me to write a personal statement for the application. After I was rejected by all UK universities, I suspected that my personal statement earlier might be poor so I had to make some changes to it before using it to apply for NUMed Malaysia. At that time, I was quite busy preparing for my A2 Trial Examination. I decided to wait until after the A2 Trial Examination before I start writing the personal statement. At the same time, Perdana required me to submit a health examination report from my doctor. My doctor told me that the report would only be out a few weeks later.

At that time, many of my friends who applied to UK universities had received offers from at least one university. That made me want to have an offer from a UK university as well. Although I could not apply to any universities for Medicine course through UCAS Extra, I realised that I could still apply for other courses. I decided to apply to Kingston University London for Pharmacy course. Since Kingston is a very low ranked university, my chance of getting an offer should be quite high. However, even if they offered me a place, it is highly unlikely that I would be accepting it. What I wanted was just an offer from a UK university.

On 5 March 2014, out of my expectation, HKU sent me an email inviting me to attend an interview in Kuala Lumpur. I was very happy because that was the first time I was shortlisted for interview by a university. Moreover, I did not have to go to Hong Kong to attend the interview. Then on 7 March 2014, I received a phone call from IMU. IMU asked me to choose an interview date and I chose 29 May 2014 which was one week after my A2 Final Examination. I attended the interview for HKU on 16 March 2014. This was the first real interview that I attended. It consisted of both group and individual interview. The group interview was quite difficult, while the individual interview was easy. Later on that month, my health examination report for Perdana was finally out. I submitted the application for Perdana on 31 March 2014. Soon after that, Perdana invited me to attend an interview.

After my A2 Trial Examination, I wanted to write the personal statement for NUMed Malaysia. This time, I asked one of my friend who had a lot of experience in this for help. I showed her the personal statement that I used for my UCAS application earlier and asked her to help make the necessary changes to it. However, my friend said that my previous personal statement was very poor and I should completely rewrite the personal statement. My A2 Final Examination would be starting soon so I was busy doing revision at that time. Therefore, I decided to write the personal statement only after the examination.

On 15 April 2014, I received an offer from Kingston for Pharmacy course. Even though Kingston is a low ranked university and the offer was not for Medicine course, I still felt happy because at least my UCAS application wasn't a complete failure. However, I would not be accepting the offer. Then on 25 April 2014, I attended the interview for Perdana. The interview was moderately difficult and I was quite confident of being offered a place. However, I received a letter from Perdana on 6 May 2014 which stated that I was rejected by them. I felt extremely disappointed. My parents were also disappointed. The fact that I was rejected even by a local university meant that my interview skills was really poor. Actually, one of my close friend also attended an interview for another university on the sane day as my interview for Perdana, and although he said that his interview was very difficult, he was successful in getting an offer.

Soon after that, it was my A2 Final Examination. My focus on doing revision for the exam partly helped reduce my disappointment. I was worried that other universities might also reject me due to my poor interview skills, so I also applied to SEGi University as a backup option. Since the ranking of SEGi is not high, I felt that my chance of getting an offer should be quite high. I submitted the application on 19 May 2014. After the exam ended, I started writing the personal statement for NUMed Malaysia. I rewrote the whole personal statement from scratch. After reading this personal statement, my friend said that it was a great improvement over the previous one but it was still not good enough. With her help, I corrected a part of the personal statement every day.

On 29 May 2014, I attended the interview for IMU. The interview was not difficult but I was not too confident of being offered a place because I was rejected by Perdana earlier. I was quite worried because if IMU rejected me, it is very likely that I would also be rejected by other universities. I kept praying that I would get an offer from IMU. On 31 May 2014, IMU telephoned me to inform me that they had offered me a place for Medicine. I felt very happy and relieved about that. I then received the conditional offer letter on 3 June 2014. After that, on 4 June 2014, SEGi telephoned me and asked me to attend an interview. I chose to be interviewed in late July.

On 5 June 2014, I finished making all the necessary corrections for my personal statement for NUMed Malaysia and my friend told me that it was good enough to be submitted. I submitted the application to NUMed Malaysia on that day. Then on 9 June 2014, NUMed Malaysia sent me an email which states that I had been shortlisted for interview. This proved that the personal statement really played an important role in the application process. I attended the interview for NUMed Malaysia on 25 June 2014. The interview was not difficult but again, I was not too confident of getting an offer. I really liked NUMed Malaysia after going there for the interview so I hoped that I would be offered a place. However, I did not feel too worried about that because even if I was rejected, I could still study Medicine at IMU.

On 26 June 2014, I received a conditional offer from NUMed Malaysia. I felt very happy, because for the first time I was offered a place for Medicine by a UK university, even though it was the Malaysia campus. This also proved that my interview skills was not too bad. However, the conditions of the offer was 3A in A level including Chemistry and Biology. This made me feel a bit worried as I was not 100% confident of getting A for Biology. After receiving offers from both IMU and NUMed Malaysia, I regretted applying to SEGi earlier. However, I had paid the non-refundable application fee so I decided to just attend the interview. I could also use that as an opportunity to practise and improve my interview skills. On 25 July 2014, my offer from Kingston for Pharmacy was automatically withdrawn because I did not accept it before the deadline. Then on 5 August 2014, I attended the interview for SEGi. The interview was not difficult, but it was not as easy as what I had expected and it lasted for a long time. SEGi then telephoned me on 8 August 2014 to tell me that they offered me a place.

On 12 August 2014, my actual A Level results was out and I obtained 4A*. I was very happy because I met the conditions of the offer from NUMed Malaysia. I sent my results to NUMed Malaysia, HKU and IMU. Both NUMed Malaysia and IMU then converted my conditional offer to unconditional offer. However, HKU still did not reply me. On 15 August 2014, I informed SEGi that I no longer wanted to study there. After that, I also telephoned IMU on 21 August 2014 to tell them to withdraw the offer. Then on 27 August 2014, HKU finally rejected me. They said that it was because the application to HKU was too competitive. I did not feel too disappointed about that since I was offered a place by NUMed Malaysia which is also a very good university. 

With that, all the universities that I had applied to have replied me. I made my final decision to study Medicine course at NUMed Malaysia and I accepted its unconditional offer on 29 August 2014. I started studying at NUMed Malaysia on 22 September 2014.

From this story, it is clear that getting the best academic results will not guarantee you a place at any university, especially for competitive courses like Medicine. Other factors such as interview performance and personal statement are also very important. To increase your chance of being offered a place, you should apply to as many universities as possible. Hope everyone will learn something from this story.

Tuesday, 30 September 2014

Tips for Cambridge International AS and A Level Examination

I scored 4A* for my AS Level in October 2013 and for my A Level in May 2014. The 4 subjects I took were Mathematics, Chemistry, Physics and Biology. Here, I am sharing the tips for these subjects in AS and A Level. These tips are intended for all students sitting for the Cambridge International AS and A Level. They are also intended for students sitting for the Brunei-Cambridge AS and A Level. Please open the links below to view the tips for each subject.

AS & A Level Mathematics:

AS & A Level Chemistry:

AS & A Level Physics:

AS & A Level Biology:

Tips for other subjects are not available.

If you are looking for tips for SPM examination, you can find it here:

Tuesday, 9 September 2014

Tips for Cambridge International AS and A Level Biology (9700)

I scored 4A* for my AS Level in October 2013 and for my A Level in May 2014. One of the 4 subjects I took was Biology. My percentage uniform mark for Biology was 90% in AS Level and 92% in A Level. Here, I am sharing the tips for AS and A Level Biology. These tips are intended for students who are sitting for Cambridge International AS or A Level.

Tips for other Cambridge International AS and A Level subjects can be found here:


1. Studying tips
- When your teacher is teaching in class, pay attention to what your teacher says. Make sure you understand everything taught by your teacher. If you do not understand anything, ask your teacher or friends.
- You need notes or reference books that are complete. I recommend you to use my notes. You can download my notes here:
- When studying a chapter, read through all the explanations in my notes or in the reference book sentence by sentence. Make sure that you truly understand each sentence before moving on to the next sentence. Certain topics may require understanding of earlier topics, so make sure you understand those topics. You should also try to relate them to what your teacher had taught in college or school.
- You should be actively involved in all experiments carried out in college or school because this can help improve your practical skills which are essential for Paper 3 and Paper 5.
- Then, you have to remember everything that you understood. You can memorise the sentences in my notes or in the reference book, or you can also create your own sentences that have the same meaning and memorise them. If you create your own sentences, make sure that you do not change the original meaning, do not leave out any important points and do not change the important keywords and scientific terms. However, do not just memorise without understanding. Once you have understood, it will be quite easy to remember and you will be unlikely to forget any of the points.
- For certain facts, there may be no explanation for them so it is not possible to understand them. In that case, you have to remember and memorise those facts.
- You have to regularly revise every topics again and again. When revising, go through all the explanation and facts in my notes or in the reference book. Make sure that you do not forget anything that you have understood previously. Regular and repeated revision will help you to remember all the explanation and facts for a long time.
- When you have understood all topics, you have to do past year A Level questions. After doing the questions, refer to the mark scheme and do self marking. Past year questions and mark schemes are available here:
- You should understand how the mark schemes are used. In the mark schemes for Biology, most marks are independent of any other marks, which means that they can be scored without other marks also being scored, unless otherwise stated by the mark scheme. If any scientific term is underlined or highlighted, it means that the exact term must be used in the answer and no other term is acceptable even if the meaning is the same, but grammatical variants of the term is accepted. If any non-scientific term is underlined or highlighted, it means that either the exact term or other terms with the same meaning must be used in the answer. If any words are placed in brackets, it means that the words need not be present in the answer for the mark to be scored. In the mark schemes, A means accept, I means ignore while R means reject.
- When doing revision before exam, you should first go through the subtopics that you think is more difficult or that you may have forgotten. Then, go through other topics as well if possible.
- To prepare for Biology Paper 3 and Paper 5, you should go through all the past year questions and the mark schemes. Find out how every question is marked and which points need to be included in the answers. The pattern of questions set is similar for every year and you should familiarise yourself with the pattern. Usually, the same type of questions will have similar mark scheme, so this can help you when answering exam questions. You should remember the answers for questions that are common.

2. Paper 1
- Read the question and all the options carefully. Write any rough workings on the question paper if you need to. Cancel off the options that you consider as definitely wrong. Then, choose the most suitable answer among the options.

3. Paper 2 and Paper 4
- From 2022 onwards, Paper 2 and Paper 4 consist of structured questions where you must answer all questions. Paper 4 is no longer divided into 2 sections.
- When answering, read the question and all information given carefully. Make sure that you know what the question is asking for. Answer the questions based on your knowledge and understanding on the relevant topic in Biology. Certain questions may test you on more than one topics. For some questions, you may have to apply what you have learnt in Biology in order to answer them. You have to think carefully and relate the question to what you have learnt. You may also be asked to give your own opinions.
- When writing your answer, you can use the same or similar words or sentences as those in my notes or in the reference books if possible. However, sometimes you may need to make some changes in order to suit the question. You can also answer in your own sentences that have the same meaning. If the question asks on something that is not in my notes and the reference books (the question requires you to apply what you have learnt in Biology or give your own opinion), then you have to answer in your own sentences. For all questions, your answer must be specific and not too general. Give the most suitable answer according to the question.
- You should use the correct scientific terms in your answer. Do not replace them with other terms that are inappropriate, even if their meaning are the same. You should spell all scientific terms correctly. If you can't do so, try to spell it in such a way where it sounds the same as the actual term when read out. Marks are usually not deducted for spelling errors in scientific terms as long as it still sounds the same and that it is not easily confused with other terms. If you spell a non-scientific term wrongly or if you make grammatical errors in your answer, marks will not be deducted for as long as the examiner can understand what you are writing. You are allowed to use suitable short forms in your answer, such as formula for chemical substances and symbols for units of physical quantities.
- It is not compulsory to answer in continuous writing form. You are allowed to answer in table form, point form or other suitable forms. In suitable cases, you can also use diagrams, equations or graphs in your answer.
- When answering questions on calculation, you should show all workings. You should not skip any important steps. You must also write the correct unit for the final answer if it is not provided. The number of marks allocated for the question usually shows the amount of working needed. 1 mark will be given for each important step and the final answer. Correct answer without working usually scores only 1 mark. If your final answer is wrong but some of your working is correct, you may still be given some marks. You are not allowed to write extra solutions or answers. If you do so and any of the answers or solutions is wrong, marks will be deducted. For a calculation question which requires you to use your answer from the previous question, even if your answer for the previous question is wrong and you use it for this question causing your answer for this question to be wrong, usually you will still get full marks for this question as long as your calculation for this question is correct. This is known as 'error carried forward'.
- When describing numerical data shown in a graph or table, you should quote suitable figures together with their units from the graph or table. For graph, each set of figure that you quote should include both the x value and y value and you should quote the figures accurate to half a small square.
- For questions that require explanation or description, your answer must be very detailed. You are advised to answer in complete sentences so that your answer can be easily understood. The number of marks allocated for the question usually shows the number of points needed in your answer. 1 mark is given for each correct point. Do not miss out any important points in your answer. You are allowed to write extra points in your answer, but you must be careful not to write any points that contradict one another. Marks will only be given for the correct points. For points that are not acceptable, whether they contain wrong facts or not, no mark will be given or deducted. However, for points that contradict one another, no mark will be given for both the points, even if one of them is correct. You are advised to write extra points if you are not completely sure of what the question is asking for.
- For questions that do not require explanation or description, write the answer straight away. You need not answer in complete sentences. The number of marks allocated for the question usually shows the number of answers needed. You are allowed to write extra answers, but you must be careful not to write answers that contradict one another. Marks will only be given for the correct answers. For answers that are not acceptable, whether they contain wrong facts or not, no mark will be given or deducted. However, for answers that contradict one another, no mark will be given for both the answers, even if one of them is correct.
- When drawing diagrams, make sure that all important details are included in the diagram you draw. You have to label correctly all parts in the diagram. Your diagram should be clear and neat.

4. Paper 3
- During the test, read the question and all information given carefully. Make sure that you understand the experiment given. Certain parts of the question require you to record the readings from the experiment in a table. You should draw the tables before carrying out the experiment so that you can record your readings in the table straight away during the experiment. Then, carry out the experiment by following the steps given in the question exactly. You need to apply your Biology practical skills when carrying out the experiment.
- Certain questions may require your knowledge and understanding in Biology to answer them. You may also need to give your own opinions. Your answer must be specific and not too general. Give the most suitable answer according to the question.
- When recording readings from an measuring instrument, the number of decimal places used should be equal to half of the smallest division of scale of the instrument (For example, if the instrument's smallest division of scale is 0.1, you should record the reading to the nearest 0.05, which is 2 decimal places.) For digital instruments (except digital stopwatch), the number of decimal places used should be the same as that shown on the display. The reading should be recorded to the nearest 1s for stopwatch (both analogue and digital). In all cases, do not give more or less number of decimal places. You must also write the correct units.
- When plotting graph, draw both the horizontal and vertical axis on the graph paper correctly. You should plot the independent variable on the x-axis and dependent variable on the y-axis. Label both axis correctly and state the unit (if any). Use a suitable scale for both axis and do not use any odd scales such as 3:10. Both the x-axis and y-axis need not start from 0 (unless otherwise stated by the question). The scales should be chosen such that the graph cover at least half of the graph paper. For line graphs, the markings on the scales should be 2cm apart, plot all points on the graph accurate to half a small square and the diameter of each point should not be larger than half a small square, then draw a curve or straight line that passes through all points on the graph if it is possible to do so, or if it is not possible, you can just use straight lines to join them point-to-point, and in all cases never extrapolate the line. For bar charts, draw blocks with equal width accurate to half a small square, where there must be space between the blocks and the distance between adjacent blocks should be equal, then label every block.
- For questions on microscopy, you will be required to draw plan diagrams and high power drawings. For all drawings, use pencil to draw, draw as big as possible without drawing over the text of the question and leave enough space for labels, ensure that the lines you draw are thin, single, unbroken, clear & continuous and never shade or colour. When drawing plan diagrams, use low power objective lens of the microscope, show the outlines of the tissues, ensure that the proportions of tissues in the diagram you draw is the same as what you see and do not include drawings of cells. When drawing high power drawings, use high power objective lens of the microscope, draw only what the question asks, show the outlines of the cells, ensure that the proportions of cells in the diagram you draw is the same as what you see, show the cell walls of plant cells as double lines and where plant cells touch there should be 3 lines and show any contents of cells that you can see which may be nucleus, chloroplasts, vacuoles or others. Label your diagram if required by the question. Use a ruler to draw the labelling lines.
- For any questions involving calculation, the number of significant figures of your answer should be equal to the number of significant figures of the raw value used in the calculation with the least number of significant figures. You should show all workings and do not skip any important steps. You must also write the correct unit for the final answer if it is not provided. You are not allowed to write extra solutions or answers. If you do so and any of the answers or solutions is wrong, marks will be deducted. For a calculation question which requires you to use your answer from the previous question, even if your answer for the previous question is wrong and you use it for this question causing your answer for this question to be wrong, usually you will still get full marks for this question as long as your calculation for this question is correct. This is known as 'error carried forward'.
- For questions that require explanation or description, your answer must be very detailed. You are advised to answer in complete sentences so that your answer can be easily understood. The number of marks allocated for the question usually shows the number of points needed in your answer. 1 mark is given for each correct point. Do not miss out any important points in your answer. You are allowed to write extra points in your answer, but you must be careful not to write any points that contradict one another. Marks will only be given for the correct points. For points that are not acceptable, whether they contain wrong facts or not, no mark will be given or deducted. However, for points that contradict one another, no mark will be given for both the points, even if one of them is correct. You are advised to write extra points if you are not completely sure of what the question is asking for.
- For questions that do not require explanation or description, write the answer straight away. You need not answer in complete sentences. The number of marks allocated for the question usually shows the number of answers needed. You are allowed to write extra answers, but you must be careful not to write answers that contradict one another. Marks will only be given for the correct answers. For answers that are not acceptable, whether they contain wrong facts or not, no mark will be given or deducted. However, for answers that contradict one another, no mark will be given for both the answers, even if one of them is correct.
- When drawing diagrams, make sure that all important details are included in the diagram you draw. You have to label correctly all parts in the diagram. Your diagram should be clear and neat.
- For all questions, you should use the correct practical and scientific terms in your answer. Do not replace them with other terms that are inappropriate, even if their meaning are the same. You should spell all practical and scientific terms correctly. If you can't do so, try to spell it in such a way where it sounds the same as the actual term when read out. Marks are usually not deducted for spelling errors in practical and scientific terms as long as it still sounds the same and that it is not easily confused with other terms. If you spell other terms wrongly or if you make grammatical errors in your answer, marks will not be deducted for as long as the examiner can understand what you are writing. You are allowed to use suitable short forms in your answer, such as formula for chemical substances and symbols for units of physical quantities.

5. Paper 5
- When answering, read the question and all information given carefully. Make sure that you understand the experiment given and know what the question is asking for. Answer the questions based on the experiment and its observations and results. You may need to apply your Biology practical skills to answer some questions. Certain questions may require your knowledge and understanding in Biology to answer them. You may also need to give your own opinions. For all questions, your answer must be specific and not too general. Give the most suitable answer according to the question.
- You should use the correct practical and scientific terms in your answer. Do not replace them with other terms that are inappropriate, even if their meaning are the same. You should spell all practical and scientific terms correctly. If you can't do so, try to spell it in such a way where it sounds the same as the actual term when read out. Marks are usually not deducted for spelling errors in practical and scientific terms as long as it still sounds the same and that it is not easily confused with other terms. If you spell other terms wrongly or if you make grammatical errors in your answer, marks will not be deducted for as long as the examiner can understand what you are writing. You are allowed to use suitable short forms in your answer, such as formula for chemical substances and symbols for units of physical quantities.
- It is not compulsory to answer in continuous writing form. You are allowed to answer in table form, point form or other suitable forms. In suitable cases, you can also use diagrams, equations or graphs in your answer.
- For any questions involving calculation, the number of significant figures of your answer should be equal to the number of significant figures of the raw value used in the calculation with the least number of significant figures. You should show all workings and do not skip any important steps. You must also write the correct unit for the final answer if it is not provided. You are not allowed to write extra solutions or answers. If you do so and any of the answers or solutions is wrong, marks will be deducted. For a calculation question which requires you to use your answer from the previous question, even if your answer for the previous question is wrong and you use it for this question causing your answer for this question to be wrong, usually you will still get full marks for this question as long as your calculation for this question is correct. This is known as 'error carried forward'.
- For questions that require explanation or description, your answer must be very detailed. You are advised to answer in complete sentences so that your answer can be easily understood. The number of marks allocated for the question usually shows the number of points needed in your answer. 1 mark is given for each correct point. Do not miss out any important points in your answer. You are allowed to write extra points in your answer, but you must be careful not to write any points that contradict one another. Marks will only be given for the correct points. For points that are not acceptable, whether they contain wrong facts or not, no mark will be given or deducted. However, for points that contradict one another, no mark will be given for both the points, even if one of them is correct. You are advised to write extra points if you are not completely sure of what the question is asking for.
- For questions that do not require explanation or description, write the answer straight away. You need not answer in complete sentences. The number of marks allocated for the question usually shows the number of answers needed. You are allowed to write extra answers, but you must be careful not to write answers that contradict one another. Marks will only be given for the correct answers. For answers that are not acceptable, whether they contain wrong facts or not, no mark will be given or deducted. However, for answers that contradict one another, no mark will be given for both the answers, even if one of them is correct.
- When drawing diagrams, make sure that all important details are included in the diagram you draw. You have to label correctly all parts in the diagram. Your diagram should be clear and neat.
- When plotting graph, draw both the horizontal and vertical axis on the graph paper correctly. You should plot the independent variable on the x-axis and dependent variable on the y-axis. Label both axis correctly and state the unit (if any). Use a suitable scale for both axis and do not use any odd scales such as 3:10. Both the x-axis and y-axis need not start from 0 (unless otherwise stated by the question). The scales should be chosen such that the graph cover at least half of the graph paper. For line graphs, the markings on the scales should be 2cm apart, plot all points on the graph accurate to half a small square and the diameter of each point should not be larger than half a small square, then draw a curve or straight line that passes through all points on the graph if it is possible to do so, or if it is not possible, you can just use straight lines to join them point-to-point, and in all cases never extrapolate the line. For bar charts, draw blocks with equal width accurate to half a small square, where there must be space between the blocks and the distance between adjacent blocks should be equal, then label every block. After that, draw the error bars based on the standard error or standard deviation if required by the question.
- For the question on planning experiment, when writing the procedure, you must include the steps to change the independent variable, measure the dependent variable and control the constant variable, as well as other steps required to set up the apparatus. You should also state the potential safety hazards when carrying out the experiment and the ways to avoid them. If there is no significant safety hazard, just state in your answer 'This is a low risk experiment'. Besides, you have to state the ways to improve the reliability of the experiment such as repeating the experiment and calculating the mean or identifying anomalies. In the procedure, you should state the amount and concentration of the substances used. You are advised to answer in complete sentences so that your answer can be easily understood. You do not need to draw the diagram of set-up apparatus.


Tips for other Cambridge International AS and A Level subjects can be found here:

Monday, 8 September 2014

Tips for Cambridge International AS and A Level Chemistry (9701)

I scored 4A* for my AS Level in October 2013 and for my A Level in May 2014. One of the 4 subjects I took was Chemistry. My percentage uniform mark for Chemistry was 96% in AS Level and 93% in A Level. Here, I am sharing the tips for AS and A Level Chemistry. These tips are intended for students who are sitting for Cambridge International AS or A Level.

Tips for other Cambridge International AS and A Level subjects can be found here:


1. Studying tips
- When your teacher is teaching in class, pay attention to what your teacher says. Make sure you understand everything taught by your teacher. If you do not understand anything, ask your teacher or friends.
- You need notes or reference books that are complete. I recommend you to use my notes. You can download my notes here:
- When studying a chapter, read through all the explanations in my notes or in the reference book sentence by sentence. Make sure that you truly understand each sentence before moving on to the next sentence. Certain topics may require understanding of earlier topics, so make sure you understand those topics. You should also try to relate them to what your teacher had taught in college or school.
- You should be actively involved in all experiments carried out in college or school because this can help improve your practical skills which are essential for Paper 3 and Paper 5.
- Then, you have to remember everything that you understood. You can memorise the sentences in my notes or in the reference book, or you can also create your own sentences that have the same meaning and memorise them. If you create your own sentences, make sure that you do not change the original meaning, do not leave out any important points and do not change the important keywords and scientific terms. However, do not just memorise without understanding. Once you have understood, it will be quite easy to remember and you will be unlikely to forget any of the points.
- For certain facts, there may be no explanation for them so it is not possible to understand them. In that case, you have to remember and memorise those facts.
- For the calculations, you need to know how to apply what you have learnt and use the correct formula to solve the questions. Go through all the example questions in my notes or in the reference book. Make sure that you understand how every question is solved.
- You have to regularly revise every topics again and again. When revising, go through all the explanation, facts and examples for calculation questions in my notes or in the reference book. Make sure that you do not forget anything that you have understood previously. Regular and repeated revision will help you to remember all the explanation and facts for a long time.
- When you have understood all topics, you have to do past year A Level questions. After doing the questions, refer to the mark scheme and do self marking. Past year questions and mark schemes are available here:
- You should understand how the mark schemes are used. In the mark schemes for Chemistry, most marks are independent of any other marks, which means that they can be scored without other marks also being scored, unless otherwise stated by the mark scheme. If any scientific term is underlined or highlighted, it means that the exact term must be used in the answer and no other term is acceptable even if the meaning is the same, but grammatical variants of the term is accepted. If any non-scientific term is underlined or highlighted, it means that either the exact term or other terms with the same meaning must be used in the answer. If any words are placed in brackets, it means that the words need not be present in the answer for the mark to be scored. In the mark schemes, A means accept, I means ignore while R means reject.
- When doing revision before exam, you should first go through the subtopics that you think is more difficult or that you may have forgotten. Then, go through other topics as well if possible.
- To prepare for Chemistry Paper 3 and Paper 5, you should go through all the past year questions and the mark schemes. Find out how every question is marked and which points need to be included in the answers. The pattern of questions set is similar for every year and you should familiarise yourself with the pattern. Usually, the same type of questions will have similar mark scheme, so this can help you when answering exam questions. You should remember the answers for questions that are common.

2. Paper 1
- Read the question and all the options carefully. Write any rough workings on the question paper if you need to. Cancel off the options that you consider as definitely wrong. Then, choose the most suitable answer among the options.

3. Paper 2 and Paper 4
- When answering, read the question and all information given carefully. Make sure that you know what the question is asking for. Answer the questions based on your knowledge and understanding on the relevant topic in Chemistry. Certain questions may test you on more than one topics. For some questions, you may have to apply what you have learnt in Chemistry in order to answer them. You have to think carefully and relate the question to what you have learnt. You may also be asked to give your own opinions.
- When writing your answer, you can use the same or similar words or sentences as those in my notes or in the reference books if possible. However, sometimes you may need to make some changes in order to suit the question. You can also answer in your own sentences that have the same meaning. If the question asks on something that is not in my notes and the reference books (the question requires you to apply what you have learnt in Chemistry or give your own opinion), then you have to answer in your own sentences. For all questions, your answer must be specific and not too general. Give the most suitable answer according to the question.
- You should use the correct scientific terms in your answer. Do not replace them with other terms that are inappropriate, even if their meaning are the same. You should spell all scientific terms correctly. If you can't do so, try to spell it in such a way where it sounds the same as the actual term when read out. Marks are usually not deducted for spelling errors in scientific terms as long as it still sounds the same and that it is not easily confused with other terms. If you spell a non-scientific term wrongly or if you make grammatical errors in your answer, marks will not be deducted as long as the examiner can understand what you are writing. You are allowed to use suitable short forms in your answer, such as formula for chemical substances and symbols for units of physical quantities.
- It is not compulsory to answer in continuous writing form. You are allowed to answer in table form, point form or other suitable forms. In suitable cases, you can also use diagrams, equations or graphs in your answer.
- When answering questions on calculation, you should show all workings. You should not skip any important steps. You must also write the correct unit for the final answer if it is not provided. You are advised to write down the formula used to solve the question, even though it is not compulsory to do so. The number of marks allocated for the question usually shows the amount of working needed. 1 mark will be given for each important step and the final answer. Correct answer without working usually scores only 1 mark. If your final answer is wrong but some of your working is correct, you may still be given some marks. You are not allowed to write extra solutions or answers. If you do so and any of the answers or solutions is wrong, marks will be deducted. When copying figures from the question or from your answer for the previous part of the question, be careful not to copy wrongly. For a calculation question which requires you to use your answer from the previous question, even if your answer for the previous question is wrong and you use it for this question causing your answer for this question to be wrong, usually you will still get full marks for this question as long as your calculation for this question is correct. This is known as 'error carried forward'.
- Usually, you should give the final answer to 3 significant figures. Do not write your final answer as a fraction or in surd form. However, if the question asks you to give your answer to a specific number of significant figures, then you must follow the instruction, or if the question states that you must give your answer to a suitable number of significant figures, then the number of significant figures of your answer should be equal to the number of significant figures of the raw value used in the calculation with the least number of significant figures.
-  For questions that require explanation or description, your answer must be very detailed. You are advised to answer in complete sentences so that your answer can be easily understood. The number of marks allocated for the question usually shows the number of points needed in your answer. 1 mark is given for each correct point. Do not miss out any important points in your answer. You are allowed to write extra points in your answer, but you must be careful not to write any points with wrong facts. Marks will only be given for the correct points. For points that are irrelevant but does not contain wrong facts, no mark will be given or deducted. However, for points that contain wrong facts, marks may be deducted.
- For questions that do not require explanation or description, write the answer straight away. You need not answer in complete sentences. The number of marks allocated for the question usually shows the number of answers needed. If the question states the number of answers you have to write, then you are not allowed to write extra answers. If you do so, marks may not be given for the extra answers, and marks may be deducted if any of them is wrong. If the question does not state the number of answers you have to write, you are allowed to write extra answers, but you must be careful not to write any answer with wrong facts. Marks will only be given for the correct answers. For answers that are irrelevant but does not contain wrong facts, no mark will be given or deducted. However, for answers that contain wrong facts, marks may be deducted.
- When drawing diagrams, make sure that all important details are included in the diagram you draw. You have to label correctly all parts in the diagram. Your diagram should be clear and neat.

4. Paper 3
- During the test, read the question and all information given carefully. Make sure that you understand the experiment given. Certain parts of the question require you to record the readings from the experiment in a table. You should draw the tables before carrying out the experiment so that you can record your readings in the table straight away during the experiment. Then, carry out the experiment by following the steps given in the question exactly. You need to apply your Chemistry practical skills when carrying out the experiment.
- Certain questions may require your knowledge and understanding in Chemistry to answer them. You may also need to give your own opinions. Your answer must be specific and not too general. Give the most suitable answer according to the question.
- When recording readings from an measuring instrument, the number of decimal places used should be equal to half of the smallest division of scale of the instrument (For example, if the instrument's smallest division of scale is 0.1, you should record the reading to the nearest 0.05, which is 2 decimal places.) For digital instruments (except digital stopwatch), the number of decimal places used should be the same as that shown on the display. The reading should be recorded to the nearest 1s for stopwatch (both analogue and digital). In all cases, do not give more or less number of decimal places. You must also write the correct units.
- For questions on titration, you should first perform a rough titration, then perform 2 accurate titrations. Record the initial burette reading and final burette reading for each titration, then calculate the titre. You should record everything in a table. All readings should be recorded to 2 decimal places. The titre for the 2 accurate titrations should not differ by more than 0.10cm3. Then, calculate the mean titre for the 2 accurate titrations. The mean should be given to 2 decimal places.
- When plotting graph, draw both the horizontal and vertical axis on the graph paper correctly. Label both axis correctly and state the unit (if any). Use a suitable scale for both axis and do not use any odd scales such as 3:10. Both the x-axis and y-axis need not start from 0 (unless otherwise stated by the question). The scales should be chosen such that the points plotted on graph cover at least half of the graph paper. Plot all points on the graph accurately. The points should be accurate to half a small square. For all the points, their diameter should not be larger than half a small square. Then, draw the correct straight line or curve. When drawing the straight line or curve, it should pass through all points on the graph if possible. If this is not possible, the line or curve should pass through as many points on the graph as possible, all the points should be close to it and the number of points above and below the line or curve should be almost equal. When determining the gradient of a straight-line graph, choose 2 points on the line and draw a triangle. The distance between the 2 points chosen should be at least half the length of the line.
- For questions on qualitative analysis, for each chemical test, you should use about 1cm depth or 2cm3 of each solution unless otherwise stated by the question. You have to record the full observations. State if there is any colour change or if precipitate forms. For any colour change, indicate both the initial and final colour, as well as the stage in which the change occurs if more than one reagents are added. If precipitate forms, state the colour of precipitate and whether it is soluble in excess of the reagent added, and if it is soluble state the colour of the solution formed. If you see any bubbles formed, it means that gas is released, and you should carry out gas tests to determine what the gas is. Only gas tests in the Qualitative Analysis Notes at the last page of question paper should be carried out. The gas can be any one of the 6 gases, but based on the type of reagents added and your experience in doing Chemistry practical work, you may be able to predict the type of gas released and thus choose the appropriate gas test to be carried out (For example, if a metal is added to an unknown solution and gas is released, it is likely that the solution is an acid and thus hydrogen gas is released, so you should carry out the gas test for hydrogen). State that effervescence occurs and state the observations of the gas test which is positive and the type of gas released. When determining the type of an unknown chemical, it should be based on your observations of the chemical tests carried out and refer to the Qualitative Analysis Notes at the last page of question paper.
- For any questions involving calculation, the number of significant figures of your answer should be equal to or one more than the number of significant figures of the raw value used in the calculation with the least number of significant figures. You should show all workings and do not skip any important steps. You must also write the correct unit for the final answer if it is not provided. You are not allowed to write extra solutions or answers. If you do so and any of the answers or solutions is wrong, marks will be deducted. For a calculation question which requires you to use your answer from the previous question, even if your answer for the previous question is wrong and you use it for this question causing your answer for this question to be wrong, usually you will still get full marks for this question as long as your calculation for this question is correct. This is known as 'error carried forward'.
- For questions that require explanation or description, your answer must be very detailed. You are advised to answer in complete sentences so that your answer can be easily understood. The number of marks allocated for the question usually shows the number of points needed in your answer. 1 mark is given for each correct point. Do not miss out any important points in your answer. You are allowed to write extra points in your answer, but you must be careful not to write any points with wrong facts. Marks will only be given for the correct points. For points that are irrelevant but does not contain wrong facts, no mark will be given or deducted. However, for points that contain wrong facts, marks may be deducted.
- For questions that do not require explanation or description, write the answer straight away. You need not answer in complete sentences. The number of marks allocated for the question usually shows the number of answers needed. If the question states the number of answers you have to write, then you are not allowed to write extra answers. If you do so, marks may not be given for the extra answers, and marks may be deducted if any of them is wrong. If the question does not state the number of answers you have to write, you are allowed to write extra answers, but you must be careful not to write any answer with wrong facts. Marks will only be given for the correct answers. For answers that are irrelevant but does not contain wrong facts, no mark will be given or deducted. However, for answers that contain wrong facts, marks may be deducted.
- When drawing diagrams, make sure that all important details are included in the diagram you draw. You have to label correctly all parts in the diagram. Your diagram should be clear and neat.
- For all questions, you should use the correct practical and scientific terms in your answer. Do not replace them with other terms that are inappropriate, even if their meaning are the same. You should spell all practical and scientific terms correctly. If you can't do so, try to spell it in such a way where it sounds the same as the actual term when read out. Marks are usually not deducted for spelling errors in practical and scientific terms as long as it still sounds the same and that it is not easily confused with other terms. If you spell other terms wrongly or if you make grammatical errors in your answer, marks will not be deducted for as long as the examiner can understand what you are writing. You are allowed to use suitable short forms in your answer, such as formula for chemical substances and symbols for units of physical quantities.

5. Paper 5
- When answering, read the question and all information given carefully. Make sure that you understand the experiment given and know what the question is asking for. Answer the questions based on the experiment and its observations and results. You may need to apply your Chemistry practical skills to answer some questions. Certain questions may require your knowledge and understanding in Chemistry to answer them. You may also need to give your own opinions. For all questions, your answer must be specific and not too general. Give the most suitable answer according to the question.
- You should use the correct practical and scientific terms in your answer. Do not replace them with other terms that are inappropriate, even if their meaning are the same. You should spell all practical and scientific terms correctly. If you can't do so, try to spell it in such a way where it sounds the same as the actual term when read out. Marks are usually not deducted for spelling errors in practical and scientific terms as long as it still sounds the same and that it is not easily confused with other terms. If you spell other terms wrongly or if you make grammatical errors in your answer, marks will not be deducted for as long as the examiner can understand what you are writing. You are allowed to use suitable short forms in your answer, such as formula for chemical substances and symbols for units of physical quantities.
- It is not compulsory to answer in continuous writing form. You are allowed to answer in table form, point form or other suitable forms. In suitable cases, you can also use diagrams, equations or graphs in your answer.
- For any questions involving calculation, the number of significant figures of your answer should be equal to or one more than the number of significant figures of the raw value used in the calculation with the least number of significant figures. If you are in doubt, give your answer to 3 significant figures. You should show all workings and do not skip any important steps. You must also write the correct unit for the final answer if it is not provided. You are not allowed to write extra solutions or answers. If you do so and any of the answers or solutions is wrong, marks will be deducted. For a calculation question which requires you to use your answer from the previous question, even if your answer for the previous question is wrong and you use it for this question causing your answer for this question to be wrong, usually you will still get full marks for this question as long as your calculation for this question is correct. This is known as 'error carried forward'.
- For questions that require explanation or description, your answer must be very detailed. You are advised to answer in complete sentences so that your answer can be easily understood. The number of marks allocated for the question usually shows the number of points needed in your answer. 1 mark is given for each correct point. Do not miss out any important points in your answer. You are allowed to write extra points in your answer, but you must be careful not to write any points with wrong facts. Marks will only be given for the correct points. For points that are irrelevant but does not contain wrong facts, no mark will be given or deducted. However, for points that contain wrong facts, marks may be deducted.
- For questions that do not require explanation or description, write the answer straight away. You need not answer in complete sentences. The number of marks allocated for the question usually shows the number of answers needed. If the question states the number of answers you have to write, then you are not allowed to write extra answers. If you do so, marks may not be given for the extra answers, and marks may be deducted if any of them is wrong. If the question does not state the number of answers you have to write, you are allowed to write extra answers, but you must be careful not to write any answer with wrong facts. Marks will only be given for the correct answers. For answers that are irrelevant but does not contain wrong facts, no mark will be given or deducted. However, for answers that contain wrong facts, marks may be deducted.
- When drawing diagrams, make sure that all important details are included in the diagram you draw. You have to label correctly all parts in the diagram. Your diagram should be clear and neat.
- When plotting graph, draw both the horizontal and vertical axis on the graph paper correctly. Label both axis correctly and state the unit (if any). Use a suitable scale for both axis and do not use any odd scales such as 3:10. Both the x-axis and y-axis need not start from 0 (unless otherwise stated by the question). The scales should be chosen such that the points plotted on graph cover at least half of the graph paper. Plot all points on the graph accurately. The points should be accurate to half a small square. For all the points, their diameter should not be larger than half a small square. Then, draw the correct straight line or curve. When drawing the straight line or curve, it should pass through as many points on the graph as possible, all the points should be close to it and the number of points above and below the line or curve should be almost equal. However, usually one or more points on the graph are anomalous, which should be ignored when drawing the straight line or curve. The line or curve should not be deviated to accommodate them.
- For the question which asks you to suggest the reason for the anomalous points on the graph, common reasons are that a particular measurement is done before or after the moment it should be done, the actual value of a quantity is higher or lower than the measured value, incomplete oxidation/reduction, incomplete decomposition, loss of water/chemical, a compound has decomposed or other similar reasons. Note that these are only the general answers, but you have to give more specific answers based on the question.


Tips for other Cambridge International AS and A Level subjects can be found here:

Saturday, 6 September 2014

Tips for Cambridge International AS and A Level Physics (9702)

I scored 4A* for my AS Level in October 2013 and for my A Level in May 2014. One of the 4 subjects I took was Physics. My percentage uniform mark for Physics was 93% in AS Level and 95% in A Level. Here, I am sharing the tips for AS and A Level Physics. These tips are intended for students who are sitting for Cambridge International AS or A Level.

Tips for other Cambridge International AS and A Level subjects can be found here:


1. Studying tips
- When your teacher is teaching in class, pay attention to what your teacher says. Make sure you understand everything taught by your teacher. If you do not understand anything, ask your teacher or friends.
- You need notes or reference books that are complete. I recommend you to use my notes. You can download my notes here:
- When studying a chapter, read through all the explanations in my notes or in the reference book sentence by sentence. Make sure that you truly understand each sentence before moving on to the next sentence. You also need to know and understand all formulas. Certain topics may require understanding of earlier topics, so make sure you understand those topics. You should also try to relate them to what your teacher had taught in college or school.
- You should be actively involved in all experiments carried out in college or school because this can help improve your practical skills which are essential for Paper 3 and Paper 5.
- Then, you have to remember everything that you understood. You can memorise the sentences in my notes or in the reference book, or you can also create your own sentences that have the same meaning and memorise them. If you create your own sentences, make sure that you do not change the original meaning, do not leave out any important points and do not change the important keywords and scientific terms. However, do not just memorise without understanding. Once you have understood, it will be quite easy to remember and you will be unlikely to forget any of the points.
- For certain facts, there may be no explanation for them so it is not possible to understand them. In that case, you have to remember and memorise those facts.
- For the calculations, you need to know how to apply what you have learnt and use the correct formula to solve the questions. Go through all the example questions in my notes or in the reference book. Make sure that you understand how every question is solved.
- You have to regularly revise every topics again and again. When revising, go through all the explanation, facts and examples for calculation questions in my notes or in the reference book. Make sure that you do not forget anything that you have understood previously. Regular and repeated revision will help you to remember all the explanation and facts for a long time.
- When you have understood all topics, you have to do past year A Level questions. After doing the questions, refer to the mark scheme and do self marking. Past year questions and mark schemes are available here:
- You should understand how the mark schemes are used. In the mark schemes for Physics, there are 4 types of marks, which are M, C, A and B. The A marks are always dependent on the M marks, which means that A marks can only be scored if the M marks are also scored. If a question does not have M mark, then the A mark can be scored on its own. C marks are automatically scored if the subsequent M or A mark is scored, even if the points for the C marks are not written down, but if the subsequent M or A mark is not scored, then the points for the C marks must be written down in order for the C marks to be scored. On the other hand, B marks are independent of any other marks, which means that they can be scored without other marks also being scored. If any scientific term is underlined or highlighted, it means that the exact term must be used in the answer and no other term is acceptable even if the meaning is the same, but grammatical variants of the term is accepted. If any non-scientific term is underlined or highlighted, it means that either the exact term or other terms with the same meaning must be used in the answer. If any words are placed in brackets, it means that the words need not be present in the answer for the mark to be scored. In the mark schemes, A means accept, I means ignore while R means reject.
- When doing revision before exam, you should first go through the subtopics that you think is more difficult or that you may have forgotten. Then, go through other topics as well if possible.
- To prepare for Physics Paper 3 and Paper 5, you should go through all the past year questions and the mark schemes. Find out how every question is marked and which points need to be included in the answers. The pattern of questions set is similar for every year and you should familiarise yourself with the pattern. Usually, the same type of questions will have similar mark scheme, so this can help you when answering exam questions. You should remember the answers for questions that are common.
- For Physics Paper 3, I also suggest that you memorise my list of 20 common answers (see below) for the limitations and suggestions question which appears in the last part of Question 2. My list is based on the mark schemes for past year questions. Usually 3 of the 4 answers required can be found in my list, and the 1st answer in my list can be used for all experiments. Sometimes, only 2 of the 4 answers required can be found in my list, and sometimes, all the 4 answers required can be found in my list. Note that for the parts of the answers in my list that are placed in brackets, it means that you have to write those parts based on the context of the experiment.

The List of Common Answers for the Limitations and Improvements Question of Paper 3 Question 2:

(a) Two/three readings are not enough to make a valid conclusion
- Take more readings and plot a graph
Note: This answer can be used for all experiments

(b) The value of (a physical quantity) is small so the percentage uncertainty of (the quantity) is large
- (The way to make the value of the quantity larger)

(c) The movement/oscillation of (something) is affected by wind movement
- Use a wind shield when carrying out the experiment

(d) Difficult to determine the start and end of oscillation/movement of (something) because it moves too fast
- Use a video camera with slow motion feature and timer to video the experiment with scale, then view the video playback frame by frame.

(e) Difficult to release (something) without applying a force
- Use a mechanical hand to release the (thing)

(f) Difficult to shape the plasticine into the shape of (something)
- Use a mould to shape the plasticine

(g) Heat loss through the sides and bottom of beaker/container
- Use polystyrene container or insulate the beaker/container
Note: This answer should be used for experiments involving the temperature of liquid.

(h) The (measuring instrument) is not precise enough
- Use another (instrument) with greater sensitivity and precision
Note: You should state in your answer the specific degree of precision for the limitation and the improvement.

(i) The length/diameter/thickness of (something) is not uniform
- Measure the length around/along the (thing) and calculate the mean

(j) Difficult to measure (something) due to (specific reason based on experiment)
- (Suggest a better way to measure it)

(k) Parallax error when measuring (something)
- (Suggest a better way to measure it, such as use mirror scale)
Note: This answer should only be used if the measurement is difficult to make and parallax error is very likely to occur.

(l) (Something) moves
- (Way to keep it in the original position)

(m) Oscillation does not occur in one plane only
Note: No possible improvement for this limitation. You should write in your answer the improvement for any other limitation.

(n) Difficult to maintain (something) at (a particular position) / maintain ruler vertical
- Use a clamp

(o) Difficult to zero the newton-meter when used horizontally
Note: No possible improvement for this limitation. You should write in your answer the improvement for any other limitation.

(p) Friction at pulley
- Apply oil to lubricate the pulley

(q) Resistance of contacts
- Clean the contacts
Note: This answer should be used for electric experiments.

(r) Difficult to determine when (something) reach the maximum height because it remains there for too short a time
(s) Difficult to take the reading of newton-meter immediately when (something) starts to move
because it moves suddenly
(t) Difficult to start or stop the stopwatch immediately when (something) passes through (somewhere)
- Use a video camera with slow motion feature and (the measuring device) to video the experiment with scale, then view the video playback frame by frame.
Note: The same improvement can be used for limitations r, s and t.

2. Paper 1
- Read the question and all the options carefully. Write any rough workings on the question paper if you need to. Cancel off the options that you consider as definitely wrong. Then, choose the most suitable answer among the options.

3. Paper 2 and Paper 4
- When answering, read the question and all information given carefully. Make sure that you know what the question is asking for. Answer the questions based on your knowledge and understanding on the relevant topic in Physics. Certain questions may test you on more than one topics. For some questions, you may have to apply what you have learnt in Physics in order to answer them. You have to think carefully and relate the question to what you have learnt. You may also be asked to give your own opinions.
- When writing your answer, you can use the same or similar words or sentences as those in my notes or in the reference books if possible. However, sometimes you may need to make some changes in order to suit the question. You can also answer in your own sentences that have the same meaning. If the question asks on something that is not in my notes and the reference books (the question requires you to apply what you have learnt in Physics or give your own opinion), then you have to answer in your own sentences. For all questions, your answer must be specific and not too general. Give the most suitable answer according to the question.
- You should use the correct scientific terms in your answer. Do not replace them with other terms that are inappropriate, even if their meaning are the same. You should spell all scientific terms correctly. If you can't do so, try to spell it in such a way where it sounds the same as the actual term when read out. Marks are usually not deducted for spelling errors in scientific terms as long as it still sounds the same and that it is not easily confused with other terms. If you spell a non-scientific term wrongly or if you make grammatical errors in your answer, marks will not be deducted for as long as the examiner can understand what you are writing. You are allowed to use suitable short forms in your answer, especially for representing physical quantities or their units.
- It is not compulsory to answer in continuous writing form. You are allowed to answer in table form, point form or other suitable forms. In suitable cases, you can also use diagrams, equations or graphs in your answer.
- When answering questions on calculation, you should show all workings. You should not skip any important steps. You must also write the correct unit for the final answer if it is not provided. You are advised to write down the formula used to solve the question, even though it is not compulsory to do so. The number of marks allocated for the question usually shows the amount of working needed. 1 mark will be given for each important step and the final answer. In some cases, if your final answer is correct, full marks will be given and the workings will not be marked. In other cases, marks can only be given for the final answer if the marks for working are scored, where correct answer without working scores 0 mark. Whichever case, if your final answer is wrong but some of your working is correct, you may still be given some marks. You are not allowed to write extra solutions or answers. If you do so and any of the answers or solutions is wrong, marks will be deducted. When copying figures from the question or from your answer for the previous part of the question, be careful not to copy wrongly. For a calculation question which requires you to use your answer from the previous question, even if your answer for the previous question is wrong and you use it for this question causing your answer for this question to be wrong, usually you will still get full marks for this question as long as your calculation for this question is correct. This is known as 'error carried forward'. For questions on 'show', 'prove', 'derive' or similar, usually marks are only given for the workings, not the answer, so it is important that you show complete workings, and explain your workings if necessary.
- Usually, you should give the final answer to 3 significant figures. Do not write your final answer as a fraction or in surd form. However, if the question asks you to give your answer to a specific number of significant figures, then you must follow the instruction, or if the question states that you must give your answer to a suitable number of significant figures, then the number of significant figures of your answer should be equal to the number of significant figures of the raw value used in the calculation with the least number of significant figures.
- When answering questions which requires you to give an answer as well as an explanation to your answer, such as questions that say 'State and explain', 'Suggest and explain' or something similar, it is very important that you give a complete and clear explanation. Marks can only be given for the answer if the marks for explanation are scored. Therefore, correct answer without satisfactory explanation usually scores 0 mark. On the other hand, if your answer is wrong but some of your explanation is correct, you may still be given some marks. In other words, 'explain' is more important than 'state' or 'suggest'.
-  For questions that require explanation or description, your answer must be very detailed. You are advised to answer in complete sentences so that your answer can be easily understood. The number of marks allocated for the question usually shows the number of points needed in your answer. 1 mark is given for each correct point. Some of the marks (A marks) may be dependent on other marks (M marks), which means that they can only be scored if the other marks are also scored. Do not miss out any important points in your answer. You are allowed to write extra points in your answer, but you must be careful not to write any points with wrong facts. Marks will only be given for the correct points. For points that are irrelevant but does not contain wrong facts, no mark will be given or deducted. However, for points that contain wrong facts, marks may be deducted.
- For questions that do not require explanation or description, write the answer straight away. You need not answer in complete sentences. The number of marks allocated for the question usually shows the number of answers needed. If the question states the number of answers you have to write, then you are not allowed to write extra answers. If you do so, marks may not be given for the extra answers, and marks may be deducted if any of them is wrong. If the question does not state the number of answers you have to write, you are allowed to write extra answers, but you must be careful not to write any answer with wrong facts. Marks will only be given for the correct answers. For answers that are irrelevant but does not contain wrong facts, no mark will be given or deducted. However, for answers that contain wrong facts, marks may be deducted.
- When drawing diagrams, make sure that all important details are included in the diagram you draw. You have to label correctly all parts in the diagram. Your diagram should be clear and neat.

4. Paper 3
- During the test, read the question and all information given carefully. Make sure that you understand the experiment given. Certain parts of the question require you to record the readings from the experiment in a table. You should draw the tables before carrying out the experiment so that you can record your readings in the table straight away during the experiment. Then, carry out the experiment by following the steps given in the question exactly. You need to apply your Physics practical skills when carrying out the experiment.
- Certain questions may require your knowledge and understanding in Physics to answer them. You may also need to give your own opinions. Your answer must be specific and not too general. Give the most suitable answer according to the question.
- When recording readings from an measuring instrument (except metre rule, vernier calipers and micrometre screw gauge), the number of decimal places used should be equal to half of the smallest division of scale of the instrument (For example, if the instrument's smallest division of scale is 0.1, you should record the reading to the nearest 0.05, which is 2 decimal places.) For digital instruments (except digital stopwatch), the number of decimal places used should be the same as that shown on the display. The reading should be recorded to the nearest 0.1cm for metre rule, 0.01cm for vernier calipers, 0.01mm for micrometer screw gauge and 0.1s for stopwatch (both analogue and digital). In all cases, do not give more or less number of decimal places. You must also write the correct units.
- In most cases, you should take each reading twice, then calculate and record the mean of the 2 readings. Ensure that you show in your answer both readings and the calculation of their mean. However, for the part in Question 1 which requires you to record readings in a table, questions that carry only 1 mark and questions which states that repeated readings are not required, you only need to take each reading once and record it straight away.
- When plotting graph, draw both the horizontal and vertical axis on the graph paper correctly. Label both axis correctly and state the unit (if any). Use a suitable scale for both axis and do not use any odd scales such as 3:10. Both the x-axis and y-axis need not start from 0. The scales should be chosen such that the points plotted on graph cover at least half of the graph paper. The markings on the scales should not be more than 3 large squares apart. Plot all points on the graph accurately. The points should be accurate to half a small square. For all the points, their diameter should not be larger than half a small square. Then, draw the correct straight line or curve. When drawing the straight line or curve, it should pass through all points on the graph if possible. If this is not possible, the line or curve should pass through as many points on the graph as possible, all the points should be close to it and the number of points above and below the line or curve should be almost equal.
- When determining the gradient of the line of graph, choose 2 points on the line and draw a triangle. The distance between the 2 points chosen should be at least half the length of the line. When determining the y-intercept of the line of graph, if the x-axis starts from 0, you can read it off directly from the y-axis of graph, or if the x-axis does not start from 0, you should choose a point on the line, preferably one of the points that you used to calculate its gradient, and substitute its x and y values as well as the gradient into the equation y=mx+c to determine the value of c which is the y-intercept.
- For any questions involving calculation, the number of significant figures of your answer should be equal to or one more than the number of significant figures of the raw value used in the calculation with the least number of significant figures. You should show all workings and do not skip any important steps. You must also write the correct unit for the final answer if it is not provided. You are not allowed to write extra solutions or answers. If you do so and any of the answers or solutions is wrong, marks will be deducted. For a calculation question which requires you to use your answer from the previous question, even if your answer for the previous question is wrong and you use it for this question causing your answer for this question to be wrong, usually you will still get full marks for this question as long as your calculation for this question is correct. This is known as 'error carried forward'.
- For the part of Question 2 which asks you to estimate the percentage uncertainty in a particular value, in most cases the absolute uncertainty used to calculate the percentage uncertainty should be equal to twice the smallest division of scale of the instrument used to measure the value (For both analogue and digital stopwatch, the absolute uncertainty used should be 0.2s). This is because the measurement for this part is often difficult to be done accurately.
- For the part of Question 2 which asks you whether your results support the suggested relationship between 2 variables, you have to calculate the percentage difference between 2 values of a constant which is obtained in previous part of the question. The suggested relationship is supported if the percentage difference is 5% or less and not supported if the percentage difference is more than 5%.
- For the last part of Question 2 which is about limitations and improvements, I would suggest that you use answers from my list of 20 common answers (see above) that you memorised. The 1st answer in my list can be used for all experiments, so you should always use it. You should also choose other answers from my list which are relevant to the experiment. You may have to give 1 or sometimes 2 other relevant answers that are not in my list since usually not all the 4 answers required can be found in my list. You are not allowed to write more than 4 answers. If you do so, marks may not be given for the extra answers, and marks may be deducted if any of them is wrong.
- For all questions, you should use the correct practical and scientific terms in your answer. Do not replace them with other terms that are inappropriate, even if their meaning are the same. You should spell all practical and scientific terms correctly. If you can't do so, try to spell it in such a way where it sounds the same as the actual term when read out. Marks are usually not deducted for spelling errors in practical and scientific terms as long as it still sounds the same and that it is not easily confused with other terms. If you spell other terms wrongly or if you make grammatical errors in your answer, marks will not be deducted for as long as the examiner can understand what you are writing. You are allowed to use suitable short forms in your answer, especially for representing physical quantities or their units.

5. Paper 5 Question 1 (Planning Experiment)
- When answering, read the question given carefully. You have to design a suitable experiment based on the question, either to test whether the suggested relationship between 2 variables is valid or to determine the value of a constant. Your answer must include independent variable, dependent variable, variables to be kept constant, diagram of set-up apparatus, procedure, data analysis, safety precautions and additional details.
- For the independent variable and dependent variable, they can be obtained easily from the question itself and you should give one of each. For the variables to be kept constant, there is often more than one and you should give all of them that you can think of. Note that the term 'kept constant' or 'keep constant' must be used in your answer and no other terms are acceptable. You need not answer in complete sentences.
- For the diagram of set-up apparatus, show all the apparatus and material used in the experiment and label them correctly. If a diagram is provided by the question, you can use the same diagram, but it is usually not complete and you have to add other apparatus or materials to it.
- When writing the procedure, you must include the steps to measure the manipulated variable, responding variable and every variable to be kept constant. For each measurement, you should state the method and apparatus used. For some variables, you may have to measure other quantities in order to calculate them. You are advised to answer in complete sentences so that your answer can be easily understood. You should also include other steps required to set up the apparatus if you did not show them in the diagram.
- For the analysis of data, you should explain how a suitable graph should be plotted that enables you to test whether the suggested relationship between the 2 variables is valid or to determine the value of the constant. Sometimes, the graph may be a log-log graph or ln-ln graph. You should also show a sketch of the graph. Then, explain how to determine whether the suggested relationship is valid or to determine the value of the constant based on the graph. This often involves the gradient, y-intercept and rearranging of equation.
- For the safety precaution, you should state at least 2 potential safety hazards when carrying out the experiment and the ways to avoid each of them.
- For the additional details, 4 marks will be given and examples of them are how variables are kept constant, calibration of the measuring instruments and additional steps to improve the accuracy and reliability. You may have already stated some of them in other parts of your answer and it is not compulsory to write them again in this part. In this section, you should state the additional details that are not stated in other parts of your answer.
- For all parts of the question, you are allowed to write extra points in your answer, but you must be careful not to write any points with wrong facts. Marks will only be given for the correct points. For points that are irrelevant but does not contain wrong facts, no mark will be given or deducted. However, for points that contain wrong facts, marks may be deducted.
- You should use the correct practical and scientific terms in your answer. Do not replace them with other terms that are inappropriate, even if their meaning are the same. You should spell all practical and scientific terms correctly. If you can't do so, try to spell it in such a way where it sounds the same as the actual term when read out. Marks are usually not deducted for spelling errors in practical and scientific terms as long as it still sounds the same and that it is not easily confused with other terms. If you spell other terms wrongly or if you make grammatical errors in your answer, marks will not be deducted for as long as the examiner can understand what you are writing. You are allowed to use suitable short forms in your answer, especially for representing physical quantities or their units.

6. Paper 5 Question 2 (Analysis, Conclusions and Evaluation)
- When answering, read the question and all information given carefully. Make sure that you understand the experiment given and know what the question is asking for. Answer the questions based on the experiment and its observations and results. You may need to apply your Physics practical skills to answer some questions. Certain questions may require your knowledge and understanding in Physics to answer them.
- For the graph, plot all points on the graph accurately. The points should be accurate to half a small square. Then, draw the error bars based on the uncertainties of the values given in the question. After that, draw line of best fit. The line should pass through as many points on the graph as possible, all the points should be close to it and the number of points above and below the line should be almost equal. Next, draw the worst acceptable line. It should be either the steepest possible line which passes from the top of top error bar to the bottom of bottom error bar or or the shallowest possible line which passes from the bottom of top error bar to top of bottom error bar. The line must also pass through all error bars.
- When determining the gradient of line of best fit, choose 2 points on the line and draw a triangle. The distance between the 2 points chosen should be at least half the length of the line. For the uncertainty in gradient, you should also determine the gradient of worst acceptable line using the same method. The uncertainty in gradient is equal to the difference between the 2 gradients.
- When determining the y-intercept of line of best fit, usually you cannot read it off directly from the y-axis of graph since the x-axis does not start from 0. Instead, you should choose a point on the line, preferably one of the points that you used to calculate its gradient, and substitute its x and y values as well as the gradient into the equation y=mx+c to determine the value of c which is the y-intercept. For the uncertainty in y-intercept, you should also determine the y-intercept of worst acceptable line using the same method. The uncertainty in y-intercept is equal to the difference between the 2 y-intercepts.
- When calculating the uncertainty in a calculated value, use your knowledge in uncertainties that you learnt in AS Level. However, if the calculation is too complicating or if it involves logarithms, there is an alternative method. For this method, you have to determine both the maximum value and minimum value of the calculated value by using the maximum values and/or minimum values of the raw values used in the calculation of the calculated value based on their uncertainties. You have to be very careful to ensure that the maximum value and minimum value you determined are correct. The absolute uncertainty is equal to half of the difference between the maximum and minimum value.
- For any questions involving calculation, the number of significant figures of your answer should be equal to or one more than the number of significant figures of the raw value used in the calculation with the least number of significant figures. For absolute uncertainties, the number of decimal places should be equal to the number of decimal places of the value. You should show all workings and do not skip any important steps. You must also write the correct unit for the final answer if it is not provided. You are not allowed to write extra solutions or answers. If you do so and any of the answers or solutions is wrong, marks will be deducted. For a calculation question which requires you to use your answer from the previous question, even if your answer for the previous question is wrong and you use it for this question causing your answer for this question to be wrong, usually you will still get full marks for this question as long as your calculation for this question is correct. This is known as 'error carried forward'.


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