A 40.0-kg box initially at rest is pushed 5.00 m along a rough, horizontal floor with a constant applied horizontal force of 130 N. The coefficient of friction between box and floor is 0.300. Find (a) the work done by the applied force, (b) the increase in internal energy in the box–floor system as a result of friction, (c) the work done by the normal force, (d) the work done by the gravitational force, (e) the change in kinetic energy of the box, and (f) the final speed of the box.

A 27.0 kg child slides down a long slide in a playground. She starts from rest at a height h11 of 23.00 m. When she is partway down the slide, at a height h22 of 13.00 m, she is moving at a speed of 6.80 m/s.Calculate the mechanical energy lost due to friction (as heat, etc.).

7. A crate of mass 10.0 kg is pulled up a rough incline with an initial speed of 1.50 m/s. The pulling force is 100 N parallel to the incline, which makes an angle of 20.0° T with the horizontal. The coefficient of kinetic friction is 0.400, and the crate is pulled 5.00 m. (a) How much work is done by the gravitational force on the crate? (b) Determine the increase in internal energy of the crate- incline system owing to friction. (c) How much work is done by the 100-N force on the crate? (d) What is the change in kinetic energy of the crate? (e) What is the speed of the crate after being pulled 5.00 m?

A crate of mass 11.0 kg is pulled up a rough incline with an initial speed of 1.48 m/s. The pulling force is 92 N parallel to the incline, which makes an angle of 20.6° with the horizontal. The coefficient of kinetic friction is 0.400, and the crate is pulled 5.06 m. (a) How much work is done by the gravitational force on the crate? (b) Determine the increase in internal energy of the crate-incline system owing to friction. (c) How much work is done by the 92-N force on the crate? (d) What is the change in kinetic energy of the crate? (e) What is the speed of the crate after being pulled 5.06 m? m/s

A bucket begins holding 25 kgs of sand. The bucket is to be lifted to the top of a 20 meter tall building by a rope with density 0.3 kg/m. However, the bucket has a hole in it, and leaks 0.3 kgs of sand each meter it is lifted. Find the work done lifting the bucket and rope to the top of the building. Use 9.8 m/s² for gravity.

In the figure, a 2.8 kg block is accelerated from rest by a compressed spring of spring constant 620 N/m. The block leaves the spring at the spring's relaxed length and then travels over a horizontal floor with a coefficient of kinetic friction -0.241. The frictional force stops the block in distance D-8.2 m. What are (a) the increase in the thermal energy of the block-floor system, (b) the maximum kinetic energy of the block, and (c) the original compression distance of the spring? No friction

This time, the pendulum is 1.07 m long and has a mass of 3.19 kg. You give it a push away from vertical so that it starts swinging with a speed of 1.02 m/s. Due to friction at the pivot point, 1.00 Joule of the pendulum s initial kinetic energy is lost as heat during the upward swing. What maximum angle will it reach, with respect to the vertical, before falling back down?     18.1 degrees     20.5 degrees     19.3 degrees     11.4 degrees

A 51-kg box is being pushed a distance of 7.0 m across the floor by a force P→⁢ whose magnitude is 185 N. The force P→⁢ is parallel to the displacement of the box. The coefficient of kinetic friction is 0.21. Determine the work done on the box by each of the four forces that act on the box. Be sure to include the proper plus or minus sign for the work done by each force.

A hurricane wind blows across a 8m x 17m flat roof at a speed of 135  km/h.  Calculate the force exerted on the roof.  Hint:  The thickness of the roof is small, so the change in potential energy between the inside of the house and the outside can be approximated to be zero.  ρair  =1. 28 kg/ m3 .

Assume that the energy content in food can be converted to mechanical energy with 100% efficiency. How many chocolate candy bars (each with 330 kcal) would it take to climb Mount Everest (8850 m)? Assume that the mass of the climber, including equipment, is 127 kg. Round up to the nearest whole number.