Hello there

The formula for Einstein's photoelectric effect is

KE=hv-phi

KE is the kinectic energy of the electron

h is the plancks constant

v is the frequency of incident light

Phi is the work function which is the minimum amount of energy an electron require to escape from a surface.It is constant for a material.Again it is given by the formula

Phi=hv0

Where v0 is called threshold frequency which is the minimum frequency at which an electron requires to break free.