A hockey puck is at the top of a 10 m long slippery slope, that makes an angle of 30° to the horizontal and leads down to a flat hockey rink. The hockey puck is struck with a hockey stick giving it a speed of 5 m/s. What is the speed of the hockey when it reaches the bottom of the slope? Assume friction is negligible.

A spring gun has a spring constant of 50 N/m and is compressed by 5 cm. It is used to launch a ball of mass 100 g. What is the speed of the ball when it leaves the gun?  The same spring gun is used to shoot the ball vertically upward. What is the maximum height reached by the ball?

A 68.5-kg athlete leaps straight up into the air from a trampoline with an initial speed of 8.7 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? (b) Select the height at which the athlete's speed is 8.7 m/s as y = 0. What is her kinetic energy at this point? What is the gravitational potential energy associated with the athlete? (c) What is her kinetic energy at maximum height? What is the gravitational potential energy associated with the athlete? (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 child and sled with a combined mass of 32.6 kg slide down a frictionless hill, starting at the top. The sled starts from rest and acquires a speed of 6.69 m/s by the time it reaches the bottom of the hill. What is the height (in m) of the hill? Answer: m (round to the nearest hundredth)

A daredevil on a motorcycle leaves the end of a ramp with a speed of 39.6 m/s as in the figure below. If his speed is 37.1 m/s when he reaches the peak of the path, what is the maximum height that he reaches? Ignore friction and air resistance.

The ratio of the kinetic energy of object A to the kinetic energy of the object B is 2:1. The mass of object A is 2.0 kg and the mass of object B is 4.0 kg. If object A has a speed of 4.0 m/s, what is the speed of object B?

In the figure here, a small block is sent through point A with a speed of 6.9 m/s. Its path is without friction until it reaches the section of length L = 13 m, where the coefficient of kinetic friction is 0.76. The indicated heights are h1= 6.0 m and h2 = 2.4 m. What are the speeds of the block at (a) point B and (b) point C? (c) Does the block reach point D? (d) If so, what is its speed there; if not, how far through the section of friction does it travel? %3D D (a) Number Unit (b) Number Unit (c) (d) Number Unit B.

a girl and her bicycle have a total mass of 60kg. at the top of the hill her speed is 5.0m/s. The hill is 5.0 m high and 100 m long. If the force of friction as she rides down the hill is 20N, what is her speed at the bottom?

The drawing shows two boxes resting on frictionless ramps. One box is relatively light and sits on a steep ramp. The other box is heavier and rests on a ramp that is less steep. The boxes are released from rest at A and allowed to slide down the ramps. The two boxes have masses of 10 and 31 kg. If A and B are 3.0 and 1.5 m, respectively, above the ground, determine the speed of (a) the lighter box and (b) the heavier box when each reaches B. (c) What is the ratio of the kinetic energy of the heavier box to that of the lighter box at B? (a) VB= (b) VB= (c) KEheavier KElighter Number i Number i Number i VA= 0 m/s "A=0 m/s AT K HA B hg Units Units Units <

A 60.0 kg skier with an initial speed of 15 m/s coasts up a 2.50 m high rise as shown in the figure. what is her final speed given the coefficient of friction between her skies and the snow is 0.39