Monochromatic light of higher frequency is directed onto the same photoemissive surface while the intensity remains unchanged. Which statement describes how the stopping potential Vs is most likely to change?
a) Vs decreases because fewer photons strike the surface each second.
b) Vs remains unchanged because photon energy does not affect the electrons’ kinetic energy.
c) Vs increases because each photon carries more energy.
d) Vs becomes zero because the work function is exceeded by a larger margin.