Physics (AS & A Level) · Feb / March 2018 · Paper 12 · Question 21

A wave pulse moves along a stretched rope in the direction shown. [diagram of wave pulse with point P] Which diagram shows the variation with time $t$ of the displacement $s$ of the particle P in the rope?

1. A[graph of s against t: negative rectangular pulse then positive triangular spike]
2. B[graph of s against t: positive triangular spike then negative rectangular pulse]
3. C[graph of s against t: negative triangular spike then positive rectangular pulse]
4. D[graph of s against t: positive rectangular pulse then negative triangular spike]

As printed in the paper