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Read the two statements below and pick the option that best describes them. Statement I: A point mass m moving at speed v strikes a stationary point mass M. The maximum possible kinetic-energy loss in the collision equals f*(1/2 m v²), where f = m/(M + m). Statement II: The largest energy loss happens when the two masses coalesce (perfectly inelastic collision).

1. Statement I is true, Statement II is true, and Statement II correctly explains Statement I.
2. Statement I is true, Statement II is true, but Statement II is not the correct explanation of Statement I.
3. Statement I is true, Statement II is false.
4. Statement I is false, Statement II is true.

Correct answer: Statement I is false, Statement II is true.

Solution

The true maximum-loss fraction is M/(M+m), not m/(M+m), so Statement I is wrong while Statement II (perfectly inelastic gives maximum loss) is correct.

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