In the photoelectric effect, suppose that the intensity of the light is increased, while the frequency is kept constant. The frequency is greater than the minimum frequency f0. State whether each of the following will increase, decrease, or remain constant, and explain your choice.

(a) the current in the phototube
____increase
____decrease
____remain constant


(b) the number of electrons emitted per second from the metal surface

_X___increase
_____decrease
_____remain constant


(c) the maximum kinetic energy that an electron could have
____increase
____decrease
__X__remain constant


(d) the maximum momentum that an electron could have
____increase
____decrease
____remain constant


(e) the minimum de Broglie wavelength that an electron could have
____increase
____decrease
____remain constant



I have figured out the answer to b and c but I am unsure of the reason. Please explain this problem for me please so that I solve this problem. I am sure it is real simple. I have been doing physics for hours and nothing is making sense anymore. Please help!!!

1 answer

a)increase b) correct c) correct
d)KE max value is constant, and so is mass, so momemtum is also
e) minimum de Broglie wavelength goes with maximum momentum, which stays constant