during a process described by the photoelectric effect, ultraviolet light can be used to charge a piece of metal.
(a) if such light is incident on a slab of conducting material and electrons are ejected with enough energy that they escape the surface of the metal how long before the metal has a net charge of + 1.50 nC if 1.00 X 10^6 electrons are ejected per second?
(b) if 1.3eV is needed to eject an electron from the surface what is the power rating of the light beam? (assume this process is 100% efficient).