Physics (AS & A Level) · May / June 2026 · Paper 12 · Question 19

An initially unstretched spring is stretched within its limit of proportionality to a length of 80 mm. The work done stretching the spring is 0.010 J. The spring constant of the spring is $22.5\,\mathrm{N\,m^{-1}}$. What is the unstretched length of the spring?

1. A30 mm
2. B50 mm
3. C60 mm
4. D110 mm

As printed in the paper