Jack pushes an 8.0kg box is through a distance of 2.2m up a 20o frictionless incline. The applied force is parallel to the incline and the speed of the box is constant.
(a) What is the work done by the normal force?
J
(b) What is the work done by gravity?
J
(c) What is the work done by Jack?
J
(d) What is the magnitude of the force that Jack applied to the box? Use the concept of work to solve this one.
N
(e) Suppose that the box is moving up the hill at a constant velocity of 2.0 m/s. If the applied force you calculated in part d is doubled, calculate the speed of the box after it has traveled 5.0-m (with the newly applied force). Remember, work done by the ALL the forces acting on the box equals the change in kinetic energy.
m/s