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Collision fundamentals: Value of the coefficient of restitution for perfectly elastic bodies. Interpret the statement: “The coefficient of restitution for elastic bodies is one.” Choose the correct truth value.

Difficulty: Easy

True
False
True only for oblique impacts
True only if masses are equal

Correct Answer: True

Explanation:

Concept/Approach

Coefficient of restitution e is defined as the ratio of the relative speed of separation to the relative speed of approach along the line of impact.
For a perfectly elastic impact, kinetic energy is conserved and e = 1.

Common pitfall
Assuming e depends on masses; it is a property of the collision pair and impact conditions.

Final Answer
True

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