A tennis ball of mass 57g travels with velocity (56, 0, 0) m/s towards a wall.

Question

A tennis ball of mass 57g travels with velocity (56, 0, 0) m/s towards a wall. after bouncing off the wall the tennis ball is observed to be traveling with velocity (-51, 0, 0)m/s

57g = .057 kg

56 * .057 = 3.192 -51 * .057 = -2.907

A) wha is the change in momentum of the tennis ball

-2.907 - 3.192 = -6.099

B) what is the magnitude of the change of moment of the tennis ball?

sqrt(-6.099)^2 = 6.099

C) what is the change in the magnitude of the tennis ball's momentum?

How do i get the answer for C? what si the formula for it? the symbol beside the answer blank is delta l p l (with an arrow on top of the p)

Answer 1

The change in magnitude of the momentum before and after the collision is 3.192 - 2.907 kgm/s. If you divide by mass, this is the coefficient of restitution. If you square that, in this case, you get the efficiency of the bounce.