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.
Answer:
An atom cannot have 0.9 of a neutron.
Explanation:
Isotope of hydrogen is Protium, 11H, which has one proton, one electron and no neutron. Another isotope of hydrogen, deuterium has one proton, one electron and one neutron. There are no elements with 0.9 neutron. It is not possible for an element to have fraction of a neutron, the neutron is always a whole number.