OK this is about a bullet hitting a block on wheels (inelastic collision), no friction or energy losses in the problem.(adsbygoogle = window.adsbygoogle || []).push({});

I'm trying to find Velocity of the system after collision

Why is it that if I use conservation of momentum I get a different answer of V than if I used conservation of Kinetic energy.

Momentum

m1*v1=(m1+m2)*v2

K energy

0.5*m1*v1^2=0.5*(m1+m2)*v2^2

You can make up your own numbers....I just dont understand the physics!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

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# Homework Help: Conservation of energy or conservation of momentum

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