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Their centers are vertically aligned. They fall through a height h, then there's an elastic collision with the ground which reverses the velcoity of the basketball while the tennis ball is still moving down because the balls have separated a bit while falling. Next, the two balls meet in an elastic collision.

A) to what height does the tennis ball rebound?

b) How do you account for the height in A being larger than h? Does it seem like a violation of conservation of energy

2) A wad of sticky clay of mass m is hurled horizontally at a wooden block of mass M on a horizontal surface. The clay sticks to the block. After impact the block slides a distance d before coming to rest. If the coefficient of friction between the block and the surface is u. What was the speed of the clay immediately before impact?

No relevent equations!

attempt for 1) Ok, so I've done this type of problem a bunch of times... but NORMALLY I HAVE THE MASSES of the balls and the height, making it waaaaay easier. I don't see how you can find the height without knowing the height to begin with in order to calculate final velocity of sqrt(2gh).

B is easy, it's larger due to the basketball exerting a higher force (because of it's larger mass), so it isn't a violation of energy since the basketball has more energy due to it's higher mass. (1/2mv^2) m = bigger for b ball and now tennis ball is moving with that energy only with a smaller mass of itself so it's v will be higher.

I just don't know how to do A. Any help is greatly appreciated. Thanks

Attempt at #2) Same problem as A, I usually do it with numbers, If anyone can help with that, I'd be grateful. I don't get how you can just predict things like that without knowing any numbers :/