hi need help..physics...?

Question

a .050kg tennis ball approaches a rocket at 25m/s. if it is in contact with the rocket strings for 0.005s then rebounds at 25m/s. what is the average contact force between the ball and rocket?

Answer 1

This is an impulse/momentum problem. Impulse = F*t, and momentum = m*v.

The relationship is ∆(m*v) = F*∆t.

In your problem, the change in momentum is 2*(.05kg)*(25m/s). The momentum before contact is +m*v, and after it is -m*v. The change in momentum is m*v(before) - m*v(after), or 2*m*v

F = 2*.05*25/.005