A horizontal spring with a spring constant k = 126 kN/m is relaxed from an extension x = 9.3 cm back to its unstretched length. Calculate the change in potential energy in Joules to 2 s.f. Your Answer: Ancwor

202.) The forces exerted by a rubber shock absorber varies with the displacement as shown. Estimate the work done to the ball shown after it has displaced the shock absorber 8.0 cm. Has the ball gained or lost energy? O Work Rubber Shock Absorber Force (Newtons) Clearly indicate how you make your estimate. Work 1.7NM Has the ball gained or lost energy? 40 30 20 10 4 8 10 Displacement (cm)

Calculate the potential energy of a 430g book being help at 1.9m off the ground. Report your answer in J.

do on the shopping cart? W -107.5 J 2. You apply a force of 1.5 N at an angle of 34° from the vertical on a block that is sitting on a friction-less table. The force you apply causes the block to slide across the table for 1 m. How much work did you do to move the block? 0.84 J 3. An 8.5 kg package in a mail sorting room slides 20 mdown a chute that

A center throws a basketball m = 1 kg straight up with an initial speed of vo = 9.5 m's. He releases the ball at shoulder | height ho = 1.9 m. Let gravitational potential energy be zero at ground level. Give the total mechanical energy of the ball E in terms of maximum height h it reaches, the mass m, and the gravitational acceleration g. E= What is the height, hm in meters? 9 HOME

"20 kg bear slides, from rest, 8 m down a Lodgepole Pine tree, moving with a speed of 5.6 m/s just before hitting the ground. What change occurs in the gravitational potential energy of the bear Earth system during the slide?"

The spring in the above figure has a spring constant of K = 140 N/m. A 150 g block is placed against the spring which is then compress to 16 cm. A) When the block is released, how high up the slope does it rise? B) What is the kinetic energy at the highest point? C) What is the potential energy at the highest point?

1. A roller-coaster car with a mass of 1200 kg starts at rest from a point 20 m above the ground. At point B, it is 9 m above the ground. [Express your answers in kilojoules (kJ).] a. What is the initial potential energy of the car? b. What is the potential energy at point B? c. If the initial kinetic energy was zero and the work done against friction between the starting point and point B is 40 000 J (40 kJ), what is the kinetic energy of the car at point B 2. The time required for one complete cycle of a mass oscillating at the end of a spring is 0.80 s. What is the frequency of oscillation?

Tom used 100N of force to drag a 10kgs of rocks up a 15 degree hill. There is an initial velocity of 1.5 m/s. The coefficient of kinetic friction is 0.40 and the rocks is dragged 7.5m. Find the work done in gravity? The work done by friction? The work done by Tom? The change in KE? The speed of the rocks after it is dragged 7.5m?

1. The restoring force from a non-ideal spring can be described by F-250N/m A-800N/m³. (Az)³, where Az is measured from equilibrium. How much work is done compressing this spring by 10 cm?