Question

What are some examples of a coefficient of restitution?

Answer 1

Golf ball, coefficient of restitution = 0.86, steel ball bearing, coefficient of restitution = 0.60.

Explanation:

Golf ball, coefficient of restitution, `C` = 0.86. Steel ball bearing, `C` = 0.60.

`C = v_2/v_1`
(where `v_2` is the velocity immediately after the collision and `v_1` is the velocity immediately before the collision).

You can also derive an expression for `C` in terms of a height of drop and rebound (neglecting air resistance, as usual):
`C = \sqrt{\frac{h}{H}}`
(H is height of drop, h is height of rebound).

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For the golf ball we can collect the following data:
H = 92 cm.
`h_1 = 67, h_2 = 66, h_3 = 68, h_4 = 68, h_5 = 70` (all cm)

Find the average rebound height and then calculate the coefficient of restitution.

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For the ball bearing we can collect the following data:
H = 92 cm.
`h_1 = 32, h_2 = 33, h_3 = 34, h_4 = 32, h_5 = 33` (all cm)

Perform the same method as for the golf ball above.