In a photoelectric experiment, electrons are ejected from metal X and Y by light of intensity I and frequency f The potential difference V required to stop the electrons is measured for various frequencies. If Y has a greater work function than which one of the following graphs best illustrates the expected results?

According to Einstein photoelectric effect formula, we have hf=ϕ+eV, where ϕ is the work functional of metal.Work function of a metal is defined as the minimum energy required to eject an electron from its surface with zero kinetic energy.According to question,ϕY>ϕXhf0Y>hf0X[f0 = Threshold frequency]Hence, graph with higher threshold frequency for Y is the correct option.