If a ball is dropped from a height H above a hard surface, it bounces. Supposing the bounces are elastic (so no KE is lost), then the v-t and a-t graphs (↑+ve) for this motion will look like:
- v-t graph consists of parallel lines (all with gradient corresponding to downward 9.81 m s-2) when the ball is rising and falling, punctuated by vertical lines when the velocity switches direction abruptly during each bounce.
- a-t graph is a horizontal line (at −9.81 m s-2), punctuated by very large positive (upward) acceleration for very brief durations during the bounces.
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