Physics (AS & A Level) · Oct / Nov 2020 · Paper 13 · Question 20

A platform is suspended by four steel wires. Each wire is 5.0 m long and has a diameter of 3.0 mm. The Young modulus of steel is 2.1 × 10^11 Pa. The wires obey Hooke's law when a load of mass 200 kg is placed on the platform. How far will the platform descend because of the extension of the wires?

1. A1.7 × 10^-4 m
2. B4.1 × 10^-4 m
3. C1.7 × 10^-3 m
4. D6.6 × 10^-3 m

As printed in the paper