Question

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A 3.1g Ball makes a perfect inelastic collision with a second ball which is at rest. If the combined mass moves at a velocity of a quarter the original velocity Of the 3.1g ball, What is the mass of the second ball in grams?

Truck moves with a velocity of 43 m\s and collides with the stationary car with exactly 1 / 5 of its mass. If the two vehicles are locked together, calculate the magnitude of the velocity of their combined masses immediately after the collision?

A 6.8 kg Cannonball is flying at 15.8 m/s [E] when it explodes into two fragments. One 1.4kg fragments (A) Goes off at 8.1 m/s [510 S of E]. What will be the magnitude of the velocity of the second fragment (B) immediately after the explosion? Assume that no mass was lost during the explosion.