A 5.00 kg ball (ball 1), moving to the right at a velocity of +4.00 m/s on a frictionless table, collides head-on with a stationary 7.60 kg ball (ball 2). Find the final velocities of the balls if the collision is as specified below.

Question

(a) elastic collision
ball 1 = -.825
ball 2 = 3.17

(b) completely inelastic collision
ball 1
ball 2i solved part A but cant figure out how to get part B started any ideas please help thanks.

Answer 1

There may be a trick on the wording on part be. It is not universally accepted in wording, but some teachers who don't know better use "completely inelastic collision" to mean the balls are stuck togther, and have the same velocity. If you make that assumption, you can get a velocity,otherwise, it is not solvable.

Answer 2

i understand but how to i go about solving this that's what i need help in, if that assumption is made.

Answer 3

since they are inelastic, they would stick together.

Final velocities
v1 = v2

momentum is still conserved.