3. A steam engine does 2500 J of useful work to move a wheel through half a rotation. The energy provided to the steam engine by heat for this work equals 7576 J. Calculate the efficiency of the engine.

Jason and alejandro lift a chair 2 meters into the moving truck using 150 newtons of force. it takes them 3 seconds to lift the chair how much power did they use

Suppose you use a machine that gives you a mechanical advantage of 2 to achieve an output force of 30newtons what must the input force be

Ametal ball with a mass of 0.028 kg is dropped from rest at a height of 1.0 meters above the ground. assuming the energy in the ball is conserved, how much kinetic energy will the ball have when it is 0.5 meters above the ground?