Physics (AS & A Level) · Oct / Nov 2018 · Paper 12 · Question 19

A variable force is applied to ensure that a constant power is supplied to a train. Which graph best shows the variation of the force $F$ applied with the velocity $v$ of the train?

1. AGraph A: $F$ decreases as a curve with increasing $v$
2. BGraph B: $F$ increases linearly with $v$ from the origin
3. CGraph C: $F$ increases as a curve with decreasing gradient from the origin
4. DGraph D: $F$ increases as a curve with increasing gradient from the origin

As printed in the paper