Question

1) A 2 . 3 kg object moving at 7.3 m/s collides inelastically with a 4.0 kg object which is initially at rest.
What percentage of the initial kinetic energy of the system is lost during the collision?

Answer 1

Assume that total momentum is conserved, and that they have the same final velocity. Compute that velocity, V, using
2.3*7.3 = 6.3 V
V = 2.665 m/s

Compute initial and final kinetic energies.
Initial: (2.3/2)*(7.3)^2 = 61.3 J
Final: (6.3/2)*(2.665)^2 = ___ J
Compute how much KE is lost and divide it by the initial KE

Answer 2

final=22.4J
22.4J/ 61.3J (initial)