Consider the problem of returning a serve in tennis. a serve is hit at a speed of 67.7 m/s, and is hit back to the server with a speed of 40.8 m/s. the ball of mas m = 57 g is in contact with the racket for 0.01s.
(a) what is the magnitude of the impulse imparted to the ball as it is returned to the server?
(b) estimate the magnitude of the average force on the ball.

The primary benefit of taking into account a child's interests while selecting exercise activities is that the child will a. play more willing with others b. succeed at their favorite activity c. allow parents to relax afterwards d. gain motivation to exercise select the best answer from the choices provided.

Mutt and jeff are running along a path each pushing a cart loaded with rocks. if mutt's wagon has a mass two times greater than jeff's and they want to stay together, arriving at their destination at the same time, what must happen? a) jeff should slow down so mutt can catch up. b) mutt must use half as much force to push his cart. c) mutt must use twice as much force to push his cart. d) mutt and jeff will use the same force, but mutt will take bigger steps.

What causes the formation of ocean currents?