Physics (AS & A Level) · May / June 2024 · Paper 13 · Question 3

The Young modulus of the material of a wire is to be found. The Young modulus E is given by the equation shown. E = 4FL / (πd²x) The wire is extended by a known force and the following measurements are made. Which measurement has the largest effect on the uncertainty in the value of the calculated Young modulus?

1. Alength of wire before force applied, L, 2.043 ± 0.002 m
2. Bdiameter of wire, d, 0.54 ± 0.02 mm
3. Cforce applied, F, 19.62 ± 0.01 N
4. Dextension of wire with force applied, x, 5.2 ± 0.2 mm

As printed in the paper