A box of 7.11 kg starts from rest along the side of a ramp with incline 24.5 degrees. The box slides 9.71 m downhill to the bottom of the ramp and has a final speed of 5.41 m/s. a) Calculate amount of work done on the box by gravity during this motion. b) Calculate the gravitational potential energy of the box at the start of the motion. Consider the bottom of the ramp as the reference height where Eg = 0. c) Calculate the coefficient of friction between the box and the ramp.

Determine the speed of 74-kg Vinco after skiing down the hill to a height which is 43 meters below the starting location?   b) After descending the 43 m, Vinko tumbled off the track and descended another 17 m down the ski hill before finally stopping.  Determine the change in potential energy of Vinko from the top of the hill to the point at which he stops.  c) Determine the amount of cumulative work done upon Vinko's body as he crashes to a halt?

A sled plus passenger with total mass 50 kg is pulled 20 m across the snow (uk = 0.20) at constant velocity by a force directed 25° above the horizontal. Calculate the work done by the applied force. %3D Answer:

A grocery cart with a mass of 10 kg is being pushed at constant speed up a 25° ramp by a force Fp which acts parallel to the incline. (Ignore the friction) a. Draw a free-body diagram of the cart showing all the forces acting on it.  b. Find the work done by each of the forces (W, Fn, Fp) on the cart if the ramp is 7.5 m long.  Hints: The question is very similar to the question of a piano sliding down an incline discussed in class. However, here the object is pushed up the incline. The forces Fn = mgcos(0), and Fp = mgsin(0), so don't spend time getting these using Newton's 2nd law. Also, the weight is W = mg. c. Find the net work done on the cart.

A box slides down a plank of length d that makes an angle of θ with the horizontal as shown. μk is the kinetic coefficient of friction and μs is the static coefficient of friction. a) Enter an expression for the minimum angle θ (in degrees) the box will begin to slide.  b) Enter an expression for the nonconservative work done by kinetic friction as the block slides down the plank. Assume the box starts from rest and θ is large enough that it will move down the plank.

A 2kg package is moves up along a 10 m ramp AC inclined at 15' with an initial speed of 5 m/s. Knowing that the coefficient of sliding friction between the package and the incline is 0.2, answer the following questions: 10 m B 15° d 1. What force/s do/does NOT do any work on the package as it moves along the incline? 2. What is the work done by friction on the package as it moves a distance x along the incline? 3. What is the change in the kinetic energy from A to B if at position the package becomes zero? 4. What is the change in the potential energy from A to B if at position B the velocity of the package 5. What is the maximum distance that the package will move up the incline?

A woman places a 2 kg block against a horizontal spring of force constant K = 300 N/m and compresses it 9 cm. a) Find the work done by the woman and the work done by the spring.b) The block is released and leaves the spring when the spring is at its original position. Find the speed of the block when it leaves the spring.

Consider a mass m=81.6 kg sliding on a frictionless surface as shown in the figure below. It begins with a speed of vi = 1.81 m/s at a height of yi = 21.4 m above the ground. It then travels down one hill and up the next until it momentarily comes to rest with a speed vi = 0.  a) What is its kinetic energy of the mass at the start? b) What is its gravitational potential energy of the mass at the start?

At a post office, a package of mass 1.3 kg is pushed down a slanted chute with an initial speed of 1.8 m/s. The upper end of the chute if 4.0 m above the floor. When it reaches the floor, the package has a speed of 0.9 m/s. Determine the energy lost through air resistance and friction with the chute.

1) A constant horizontal force of F = 200.0 N pushes a crate of mass m = 25.0 kg, initially at rest, along a rough horizontal surface. The crate travels a total distance of 8.00 m, and the coefficient of kinetic friction between the crate and the surface is 0.250. a) What is the work done on the crate by the force F? b) How much does friction increase the internal energy of the crate-surface system ?