The front 1.20 m of a 1400 kg car is designed as a "crumple zone" that collapses to absorb the shock of a collision. (a) If a car traveling 22.0 m/s stops uniformly in 1.20 m, how long does the collision last?  s (b) What is the magnitude of the average force on the car?  N (c) What is the acceleration of the car? Express the acceleration as a multiple of the acceleration of gravity. (Indicate the direction with the sign of your answer.

An ice skater with mass = mi goes skating while carrying a bag of sand with initial mass = m0 . At one point, she gives herself a constant initial velocity v0 , and then slowly pours the sand out of the bag at a constant rate κ. Is she speeding up or slowing down? Write out an expression for the velocity as a function of time. How long does it take for her velocity to change by a factor of 2? Your answer can include mi, m0, v0, and κ.

A man ( mass = 100 kg) fall freely from rest and strikes the ground. During the collision with the ground, he comes to rest in a time of .2s. The average force exerted on her by the ground is + 2000 N, where the upward direction is taken to be the positive direction. A) from what height did he just fall? Assume the only force acting on him during the collision is that of the ground. B) suppose instead of the man, a 5 kg rubber ball was dropped from the same vertical distance and the ball bounced back conserving the linear momentum. What would be the velocity of the ball just when it bounced back?

k A 13.00 kg particle starts from the origin at time zero. Its velocity as a function of time is given by = 10t² + 1tj where is in meters per second and t is in seconds. (Use the following as necessary: t.) V (a) Find its position as a function of time. ŕ= esc 10/³1 + ²/2 2²; 3 (b) Describe its motion qualitatively. The particle starts from rest at the origin, starts moving in the y direction, and gains speed faster and faster while turning to move more and more nearly parallel to the x axis. Score: 0.06 out of 0.06 Comment: (c) Find its acceleration as a function of time. a = 20ti + lj m/s² (d) Find the net force exerted on the particle as a function of time. F= T= (e) Find the net torque about the origin exerted on the particle as a function of time. N m X X (f) Find the angular momentum of the particle as a function of time. Ľ Need Help? Read It F1 N x (g) Find the kinetic energy of the particle as a function of time. K= x kg m²/s X (h) Find the power injected into the particle as a…

Car A (800kg ) is traveling due East at 14m/s when it collides with Car B (1200kg), which is traveling due North at 10m/s. The cars lock together inelastically following the collision as shown. Car A (initial) Car B (initial) Car A & B (final) |p|x unit How fast were the vehicles moving after the collision? unit What direction did the vehicles move after the collision? ° North of East Iply unit before A B Reference after Lesson 1 2 3 W+ N S 4 5 E 6 7 8

A man claims that he can hold onto a 13.0-kg child in a head-on collision as long as he has his seat belt on. Consider this man in a collision in which he is in one of two identical cars each traveling toward the other at 50.0 mi/h relative to the ground. The car in which he rides is brought to rest in 0.07 s. (a) Find the magnitude of the average force needed to hold onto the child. N (b) Based on your result to part (a), is the man's claim valid? O This man's claim is nonsense. O This man's claim is legitimate.

Sherlock Holmes is one of the most famous detectives in fiction literature. Even with limited resources to solve crime in the 1800-1900's, Holmes could solve countless mysteries. A carriage was North-bound traveling at a leisurely pace of 5 km/hr. It collided with a Westward-bound speeding carriage and they stuck together, skidding across the dirt at an North-West direction away from the point of collision. What physics law(s) does Sherlock use to solve this mystery? Conservation of Momentum Conservation of Energy Conservation of Angular Momentum Both Conservation of Momentum and Energy OOO O

A brave but inadequate rugby player is being pushed backward by an opposing player who is exerting a force of 740 N on him. The mass of the losing player plus equipment is 88 kg, and he is accelerating at 1.8 m/s2 backward. Randomized Variables: f = 740 Nm1 = 88 kgm2 = 118 kga = 1.8 m/s2                                                        1. What is the magnitude of the force of friction, in newtons, between the losing player's feet and the grass as he slides backwards? F1 =                           2. What is the magnitude of the force, in newtons, that the winning player exerts on the ground to move forward if his mass plus equipment is 118 kg? Assume the second player has the same acceleration as the first. F2=

After falling from rest from a height of 31 m, a 0.40-kg ball rebounds upward, reaching a height of 21 m. If the contact between ball and ground lasted 2.3 ms, what average force was exerted on the ball? (Enter the magnitude.) N