1) A constant force of 9.0 kN, parallel to an inclined plane, moves a body of weight 20 kN through a distance of 40 m along the plane at constant speed. The body gains 12 m in height, as shown.

How much of the work done is dissipated as heat?

2) A person exerts a horizontal force of 600 N on a box that also experiences a friction force of 200 N.

If it takes 4.0 seconds to move the box 3.0 m, what is the average useful power?

3) A small emergency generator supplies 4.32 × 10⁸ J of electrical energy in 24 hours. What
is the average power output of the generator?

4) A motorist travelling at 10 m s^–1 can bring his car to rest in a distance of 10 m. If he had been travelling at 30 m s^–1, in what distance could he bring the car to rest using the
same braking force?

5) A car of mass m has an engine which can deliver power P. What is the minimum time in which the car can be accelerated from rest to a speed v?