A 230 g block is dropped onto a relaxed vertical spring that has a spring constant of k = 1.3 N/cm (see the figure). The block becomes attached to the spring and compresses the spring 14 cm before momentarily stopping. While the spring is being compressed, what work is done on the block by (a) the gravitational force on it and (b) the spring force? (c) What is the speed of the block just before it hits the spring? (Assume that friction is negligible.) (d) If the speed at impact is doubled, what is the maximum compression of the spring?

You drop a 2.60 kg book to a friend who stands on the ground at distance D = 12.0 m below. If your friend's outstretched hands are at distance d = 1.50 m above the ground (see the figure), (a) how much work Wg does the gravitational force do on the book as it drops to her hands? (b) What is the change AU in the gravitational potential energy of the book-Earth system during the drop? If the gravitational potential energy U of that system is taken to be zero at ground level, what is U (c) when the book is released and (d) when it reaches her hands? Now take U to be 100 J at ground level and again find (e) Wg, (f) AU, (g) U at the release point, and (h) U at her hands. (a) Number i Units (b) Number i Units (c) Number i Units (d) Number i Units (e) Number i Units (f) Number i Units (g) Number i Units (h) Number i Units > > > > > > >

In the figure below an object of mass m starts from rest on a roller coaster with negligible friction. A hA B hB C hc Ꭰ hp (a) What terms are present in the object's mechanical energy? Choose from E O Gravitational potential energy, Spring potential energy, Kinetic energy, Work done against friction O Gravitational potential energy, Spring potential energy, Kinetic energy Spring potential energy, Kinetic energy, Work done against friction, Gravitational potential energy, Kinetic energy because, there is no friction (b) Mechanical energy is conserved Only conservative forces ◆ act. (c) Calculate the speed of the object at point D (VD) in terms of the following variables: (g, ha, hD)

A 31 kg bear slides, from rest, 10 m down a lodgepole pine tree, moving with a speed of 3.0 m/s just before hitting the ground. (a) What change occurs in the gravitational potential energy of the bear-Earth system during the slide? (b) What is the kinetic energy of the bear just before hitting the ground? (c) What is the average frictional force that acts on the sliding bear?

A 65.70 kg baseball player begins his slide into second base when moving at a speed of 6.090 m/s. The coefficient of friction between his clothes and the earth is 0.7480. How much work (in Joules) is done on the runner as he slides to a stop?

You drop a 1.50 kg book to a friend who stands on the ground at distance D= 12.0 m below. If your friend's outstretched hands are at distance d = 1.30 mabove the ground (see the figure), (a) how much work W, does the gravitational force do on the book as it drops to her hands? (b) What is the change AU in the gravitational potential energy of the book-Earth system during the drop? If the gravitational potential energy Uof that system is taken to be zero at ground level, what is U (c) when the book is released and (d) when it reaches her hands? Now take U to be 100 J at ground level and again find (e) W, (f)AU. (g) U at the release point, and (h) U at her hands. (a) Number Units (b) Number Units (c) Number Units (d) Number Units (e) Number Units (f) Number Units (g) Number Units (h) Number Units >

A Net Force Fnet=(x-3x2)i + (2y2-y3)j acts on a 3.5 kg particle. a) Calculate the net work done on the particle as it moves from (1.0m,0.0m) to (1.0m,4.0m). b) At (x,y) = (1.0m,0.0m), the particle's speed is 5.0 m/s. Find the particle's speed at (x,y) = (1.0m,4.0m).

A 38 kg bear slides, from rest, 12 m down a lodgepole pine tree, moving with a speed of 5.1 m/s just before hitting the ground. (a) What change occurs in the gravitational potential energy of the bear-Earth system during the slide? (b) What is the kinetic energy of the bear just before hitting the ground? (c) What is the average frictional force that acts on the sliding bear?

A 3.6 g marble is fired vertically upward using a spring gun. The spring must be compressed 2.9 cm if the marble is to just reach a target 18 m above the marble's position on the compressed spring. (a) What is the change AU in the gravitational potential energy of the marble-Earth system during the 18 m ascent? (b) What is the change AU in the elastic potential energy of the spring during its launch of the marble? (c) What is the spring constant of the spring? (a) Number (b) Number ogres (c) Number Units Units Units

A worker pushing a 35.0-kg wooden crate at a constant speed for 13.6 m along a wood floor does 400 J of work by applying a constant horizontal force of magnitude F0 on the crate. (a) Determine the value of F0. ____N (b) If the worker now applies a force greater than F0, describe the subsequent motion of the crate. (c) Describe what would happen to the crate if the applied force is less than F0.