Physics (AS & A Level) · Oct / Nov 2020 · Paper 11 · Question 20

An unstretched rubber cord is stretched by a force. The force F is plotted against the extension x. F is slowly increased from zero, causing the cord to extend along path P. F is then reduced back to zero along path Q. What is represented by the shaded area?

1. Athe elastic energy stored in the rubber cord
2. Bthe energy that causes plastic deformation
3. Cthe energy dissipated as heat
4. Dthe work done to extend the rubber cord

As printed in the paper