A crane drops a 1.8 kg steel ball onto a steel plate. The ball's speeds just before impact and after are -7.9 m/s and 5.8 m/s, respectively. If the ball is in contact with the plate for 0.059 seconds, what average force does the ball exert on the plate during impact?

7. During a snowball fight, a 0.30-kilogram snowball traveling at a speed of 17.0 m/s hits a student in the back of the head. If the contact time is 0.10 s, what is the magnitude of the average force on the student's head? N ssf f60° Ossi 09 JS 50 ssf60

A toy car with a mass of 128 g moves to the right with a speed of 0.810 m/s. A small child drops a 30.0-g piece of clay onto the car. The clay sticks to the car and the car continues to the right. What is the change in speed of the car? Consider the frictional force between the car and the ground to be negligible. -0.15 m/s

A 105-kg rugby player is initially running at 7.5 m/s in the positive direction, but collides head-on with a padded goalpost and experiences a backward force of 1.76 × 104 N for 5.55 × 10–2 s. Calculate the final velocity in the horizontal direction of the rugby player, in meters per second.   vf =

A baseball (m= 150 g) approaches a bat horizontally at a speed of 43.9 m/s (98.2 mi/h) and is hit straight back at a speed of 52.6 m/s (118 mi/h). If the ball is in contact with the bat for a time of 1.27 ms, what is the average force exerted on the ball by the bat? Neglect the weight of the bat, since it is so much less than the force of the bat. Choose the direction of the incoming ball as the positive direction. Number i Units VO Vf

A very hard rubber ball (m = 0.6 kg) is falling vertically at 5 m/s just before it bounces on the floor. The ball rebounds back at essentially the same speed. If the collision with the floor lasts 0.05 s, what is the average force exerted by the floor on the ball? __________________ N

A 4.0 kg ball is traveling at 11.9 m/s and strikes a wall. The ball bounces off the wall with a velocity of 4.2 m/s in the opposite direction. If the ball is in contact with the wall for 0.10 seconds, then the magnitude of the average force on the ball during contact is? Enter only a numerical answer. Do not include units in the answer box, else your response will be counted as incorrect.

A 66.0-kg athlete leaps straight up into the air from a trampoline with an initial speed of 7.5 m/s. The goal of this problem is to find the maximum height she attains and her speed at half maximum height. (a) What are the interacting objects and how do they interact? This answer has not been graded yet. (b) Select the height at which the athlete's speed is 7.5 m/s as  y = 0.  What is her kinetic energy at this point? JWhat is the gravitational potential energy associated with the athlete? J(c) What is her kinetic energy at maximum height? JWhat is the gravitational potential energy associated with the athlete? J(d) Write a general equation for energy conservation in this case and solve for the maximum height. Substitute and obtain a numerical answer. m(e) Write the general equation for energy conservation and solve for the velocity at half the maximum height. Substitute and obtain a numerical answer. m/s

A 0.2-kg rubber egg bounces off an actor's roof, remaining in contact with it for 43 ms while changing the egg's velocity from 24.5 m/s directly toward the roof to 13.5 m/s directly away from it. Find the magnitude of the average force applied to the egg by the roof. (Be careful with units!) Fav= = N Record your numerical answer below, assuming three significant figures. Remember to include a "-" when necessary.

A hockey player slaps a puck into a cushion, which brings the puck to rest.  If the puck's initial velocity was +40 m/s and it has a mass of 170 g, what force does the cushion apply to the puck?  Assume the cushion acts on the puck for 0.03 s and the surface that the puck slides on is frictionless.