KCL Section 1: Uncertainty (Materials)

Question 1

What is the absolute uncertainty:
In a ruler measurement of 13.2 cm
In a reading of 2.15 kg from a set of scales
In this set of times: 42s, 43s, 47s, 41s, 45s
In a width of 0.0978 m, read by a vernier calliper
In the weight of some 10p coins: 64.77 N, 64.72 N, 64.80 N

Answer 1

0.05
0.025
3
0.00005
0.04

Question 2

What is the percentage uncertainty:

3.70 ± 0.05 cm
16.02 ± 0.08 N
592 ± 0.5 kg

Answer 2

Divide the absolute uncertainty by the measured value

0.014
5 x 10^-3
8.45 x 10^-4

Question 3

If you are adding/subtracting measurements you ___ the absolute uncertainties

Answer 3

add

Question 4

If you are multiplying/dividing measurements you ____ the percentage uncertainties

Answer 4

add

Question 5

If you are raising measurements to a power you _____ the percentage uncertainty by the power

Answer 5

multiply