Using a micrometer screw gauge, I get 3 values for the diameter,d, of a wire each with +/- 0.01mm.
What's the uncertainty for the average value for d?
Then I have to use this average value in (πd^2)/4=A. What's the % uncertainty of A?
x Turn on thread page Beta
Physics uncertainty problem watch
- Thread Starter
- 11-05-2016 12:42
- Official Rep
- 13-05-2016 14:03
Sorry you've not had any responses about this. Are you sure you've posted in the right place? Here's a link to our subject forum which should help get you more responses if you post there.
You can also find the Exam Thread list for A-levels here and GCSE here.
Just quoting in Puddles the Monkey so she can move the thread if needed
Spoiler:Show(Original post by Puddles the Monkey)
- 14-05-2016 17:56
When you've taken repeat readings, the correct way to determine the percentage uncertainty is:
( (half the range) / (average value) ) * 100
That would give you the percentage uncertainty in d. You then double this to get the uncertainty in A (due to the d being squared).