Sue can easily lift a 60-N rock with the help of a lever. When she pushes down with 20 N of force, she lifts the rock .75 meters. how far does she move her arm to do this?

In a heat engine if 1000 j of heat enters the system the piston does 500 j of work, what is the final internal energy of the system if the initial energy was 2000 j ?

Air enters a compressor operating at steady state at 1.05 bar, 300 k, with a volumetric flow rate of 93 m3/min and exits at 12 bar, 400 k. heat transfer occurs at a rate of 15.5 kw from the compressor to its surroundings. assuming the ideal gas model for air neglecting kinetic potential energy effects, determine the power in put in kw.

Which statement is true? a. kepler's laws apply only to the motion of earth. b. kepler's laws can be used to predict eclipses. c. kepler's laws are true for a central force that is directly proportional to distance. d. kepler's laws can be deduced from newton's laws of motion and gravity.