a 2 kg mass moves to the right at 2m/s and collides with a 6 kg mass?

Question

a 2 kg mass moves to the right at 2m/s and collides with a 6 kg mass moving to the left at 4m/s. if the collision is completely inelastic, what is the common velocity of the two masses after they collide, and how much energy is lost in the collision?

Answer 1

using conservation of momentum
2*2-6*4=8*v
v=-2.50 m/s

the delta ke is
(.5*2*4+.5*6*16)-.5*8*2.5^2
There are 27 J lost in the collision

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