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A 0.200 kg air-track glider moving at 1.20 m/s bumps into a 0.600 kg glider at rest.
a.) Find the total kinetic energy after collision if the collision is elastic.
b.) Find the total kinetic energy after collision if the collision is completely inelastic.
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Question

Trying to be exempt from the final, help asap? 

A 0.200 kg air-track glider moving at 1.20 m/s bumps into a 0.600 kg glider at rest. 
a.)	Find the total kinetic energy after collision if the collision is elastic.
b.)	Find the total kinetic energy after collision if the collision is completely inelastic.
Show all your work.

anonymous · Answer

a. elastic means Total KE  is unchanged = original (1/2) m v^2 by conservation of energy

b. have to conserve momentum so that m v = (m + M)v'
then calculate (1/2) (m+ M) (v')^2 = KE
completely inelastic means the masses merged