When jumping straight down, you can be seriously injured if you land stiff-legged. One way to avoid injury is to bend your knees upon landing to reduce the force of the impact. A 88.1-kg man just before contact with the ground has a speed of 3.07 m/s. (a) In a stiff- legged landing he comes to a halt in 4.70 ms. Find the magnitude of the average net force that acts on him during this time. (b) When he bends his knees, he comes to a halt in 0.219 s. Find the magnitude of the average net force now. (c) During the landing, the force of the ground on the man points upward, while the force due to gravity points downward. The average net force acting on the man includes both of these forces. Taking into account the directions of the forces, find the magnitude of the force applied by the ground on the man in part (b). (a) Number (b) Number i (c) Number i Units Units Units

On the set of a new Hollywood movie, a 74.1-kg stunt actor (Max Payne) is tossed straight out of a helicopter hovering (stationary) at a height of 43.4 meters. The stunt actor is thrown from the helicopter at a speed of 4.17 m/s, eventually landing in the water below.  Determine the stunt actor's impact speed and assume negligible air resistance. You can use the approximation that g = 10 m/s2.

After falling from rest from a height of 25 m, a 0.30-kg ball rebounds upward, reaching a height of 15 m. If the contact between ball and ground lasted 2.1 ms, what average force was exerted on the ball? (Enter the magnitude.)

After falling from rest from a height of 31 m, a 0.60-kg ball rebounds upward, reaching a height of 21 m. If the contact between ball and ground lasted 2.5 ms, what average force was exerted on the ball?

A 115kg rugby player is initially running at 5.5 m/s in the + direction, but collides with a goalpost and experiences a backward force of 1.71 × 10^4 N for 5.25 × 10^-2 s. what is the final \velocity of the rugby player in the horizontal direction

During a practice dive, a 45-kgkg diver jumped to a maximum height of 4.4 mm above the water before coming down and entering the water. She came to rest 0.40 ss after hitting the water. Determine the average force that the water exerted on her while stopping her.

Daredevil Darla has heard that to avoid injury when jumping out of her rocket she should bend her knees upon landing. Darla has a mass of 74 kg. If just before contact with the ground, she has a downward speed of 7.3 m/s, then. . .   (a) In a stiff -legged landing she comes to a halt in 2.0 ms. Find the average net force that acts on her during this time. (   b) When she bends her knees, Darla comes to a halt in 0.10 s. Find the average net force now.   (c) During the landing, there are two forces acting on Darla: the normal force from the ground points upward, while her weight force points downward. The average net force acting on Darla includes both of these forces. Taking into account the directions of the forces, find the force of the ground on Darla in parts (a) and (b).

A baseball (m = 148 g) approaches a bat horizontally at a speed of 40.7 m/s (91.1 mi/h) and is hit straight back at a speed of 51.6 m/s (115 mi/h). If the ball is in contact with the bat for a time of 1.45 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.

Michael fell asleep while driving home from school. His 1255 kg car hit a guardrail while moving at 15.98 m/s. The guardrail exerted a 6.110E4 N force on the car for 0.1233 s. After the car hit the guardrail, how fast was it moving?

A bullet is accelerated down the barrel of a gun by hot gases produced in the combustion of gun powder. What is the average force (in N) exerted on a 0.0500 kg bullet to accelerate it to a speed of 675 m/s in a time of 5.00 ms (milliseconds)? (Enter the magnitude.)