Physics (AS & A Level) · May / June 2017 · Paper 12 · Question 21

A rubber band is stretched and then relaxed to its original length. The diagram shows the force-extension graph for this process. As the force is increased, the curve follows the path OPQ to extension e. As the force is reduced, the curve follows the path QRO to return to zero extension. The area labelled X is between the curves OPQ and QRO. The area labelled Y is bounded by the curve QRO and the horizontal axis. Which statement about the process is correct?

1. AArea X is the energy which heats the band as it is stretched to extension e.
2. B(Area X + area Y) is the minimum energy required to stretch the band to extension e.
3. CArea X is the elastic potential energy stored in the band when it is stretched to extension e.
4. D(Area Y – area X) is the net work done on the band during the process.

As printed in the paper