Answer:
5) You push hard on a heavy desk and try to move it. You do work on the desk: A.- Whether you move it or not, as long as you exert a force. B.- Only if the desktop moves. C.- Only if the desktop does not move. D.- Never; the desk does work on you. E.- None of the above. CAN YOU HELP ME?
B.- Only if the desktop moves.
Explanation:
No work is done if a force is exerted but no displacement occurs. A force perpendicular to the displacement does no generate work.