Paper 1 · kinematics
A tennis ball is dropped from a particular height h. The motion of the ball is monitored over three bounces. Which graph shows how the velocity (V) is varying with time (t)?
AConstant positive velocity
BSquare-wave alternating velocity
CSawtooth velocity with decreasing peaks (linear increase then jumps)
DSquare-wave with decreasing magnitude
Explanation: During each fall velocity increases linearly (constant g); at each bounce it reverses and the peak speed decreases. This gives a sawtooth-like velocity-time graph with decreasing peaks (graph C).
ZIMSEC Physics Paper 1, June 2004, Q3

