A tennis racquet is used to bounce a tennis ball up and down. How long is the tennis racquet interacting with the tennis ball if the change in momentum is 35 kgm/s [up] and the average spring force by the racquet is 225 N?

0.16s

Explanation:

Given the following :

Average spring force by the racquet (F) = 225N

Change in momentum = 35kgm/s

To determine the change in interaction time; that is the momentary for e acting in the tennis ball ( impulse)

Recall:

F = mass(m) × acceleration(a)

Acceleration (a) = change in Velocity with time

a = change in V / time(t)

F = m * change in V / t

Ft = m* change in v

Recall m* change in v = momentum

Ft = change in momentum

225 * t = 35

t = 35 / 225

t = 0.1555555

t = 0.16s

i don't understand. explain it clearly