can anyone tell m how to decide the siginifcant fig for the answer to be ket in physics edexcel?i thought it was for the lowest in the values but edexcel has proved otherwise
- Thread Starter
- 17-05-2013 09:12
- 24-05-2013 06:53
I was always told to use the number of decimal places for the value with the smallest number of decimal places in the calculation. So 10.5 x 1.0001 = 10.5 because that's the limitation of the precision of those numbers. I'm sure it's with regards to decimal places and not significant figures though.
Also, try to make sure the answer is given in standard form with multiples of thousands (so 10^3, 10^6, 10^-3, 10^-6, etc). Some calculators will have an "ENG" button which does this for you.
At uni we usually just give 3 decimal places regardless of that fact, but I always make sure to use 5 decimal places (or 2 more decimal places than what the answer expects) in the calculation and then round to 3 decimal places when giving the answer. At each stage I give a substantially longer answer and then indicate my rounded answer. I basically just copy out the answer from the display. If they aren't happy with the number of decimal places you've used, writing down the "full" answer beside the rounded answer may just encourage them to give you some marks for the answer anyway.