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Significant figures in GCSE physics?

I'm doing IGCSE Physics with CIE, and the significant figures required for an answer are all messed up honestly. For example, on questions with forces, I have to give two significant figures, but then on another question with forces, I have to give all the figures?

Does anyone know how many significant figures I should give for each of the topic questions?
If it is not stated in the quetion, the rule we folllow in Uni is to use the same number of SF as the question does. Basically say the question is Force=5.0 and Mass=2.4 what is Acceleration? You would quote acceleration in 2 SF because that is how many the question used

Hope this helped
Its irrelevant to the topic, what the ACTUAL thing to do is, give your answer to the least amount of significant figures provided in the questions. Say the question is, a car is travelling at 8.059m/s for 4.5 seconds, what is the Distance travelled? The Speed is given to 4sf, however time is given to 2sf so the answer is to 2sf as you can not be more accurate than this. Its kinda hard to understand, let me know if and what you dont understand. And at gcse if you give it to like 4 sf i think you will always get the mark unless it tells how many to give.
(edited 5 years ago)
Reply 3
Original post by steveeem
Its irrelevant to the topic, what the ACTUAL thing to do is, give your answer to the least amount of significant figures provided in the questions. Say the question is, a car is travelling at 8.059m/s for 4.5 seconds, what is the Distance travelled? The Speed is given to 4sf, however time is given to 2sf so the answer is to 2sf as you can not be more accurate than this. Its kinda hard to understand, let me know if and what you dont understand. And at gcse if you give it to like 4 sf i think you will always get the mark unless it tells how many to give.


I think I've got it! Thank you so much!

Original post by Jay_Gatsby123
If it is not stated in the quetion, the rule we folllow in Uni is to use the same number of SF as the question does. Basically say the question is Force=5.0 and Mass=2.4 what is Acceleration? You would quote acceleration in 2 SF because that is how many the question used

Hope this helped


It did, thank you! I appreciate how quick your responses were too- I have my exam in five days and was petrified because I kept losing marks for dumb reasons on past papers. This was a genuine relief. Thank you.
Original post by Jay_Gatsby123
If it is not stated in the quetion, the rule we folllow in Uni is to use the same number of SF as the question does. Basically say the question is Force=5.0 and Mass=2.4 what is Acceleration? You would quote acceleration in 2 SF because that is how many the question used

Hope this helped

I know this post is three years old but I really can't thank you enough, I kept losing marks because I either rounded or didn't round my answers, again thank you so much.

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