Hi. Sorry if this looks too beginner-ish question.(adsbygoogle = window.adsbygoogle || []).push({});

Lets say we have two objects moving towards each other. One is heavier than another and we know it's speed. We want to find out how fast should lighter object move so that after the collision both objects would stop.

Question is, what should we use to calculate the speed of the lighter body, kinetic energy's equation or momentum's? Those two give slightly different answers.

Thank you.

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# Momentum vs Kinetic Energy.

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