Dear all,(adsbygoogle = window.adsbygoogle || []).push({});

I know the equation to conservation of momentum.

How do I show that kinetic energy is always conserved if it says that the mass of the two objects are the same.

The following is the explaination I found but I don't get part of it.

The red arrow part (attached image) is where I'm stuck on.

Thanks for the help!

pino

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# Momentum- elastic collisions

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