Question

Define the following in photoelectric effect phenomenon:
(a) (i) Work function
(ii) Stopping potential (cut-off potential)
(b) Calculate energy of photon of wavelength $3.31\mathring{A}$.

Answer 1

(a) (i) Work function is the minimum quantity of energy which is required to remove an electron to infinity from the surface of a given metal surface.

(ii) Stopping potential is defined as the potential necessary to stop any electron from photoelectric emission.

(b) Energy of photon of wavelength $\lambda$, $E=\frac{hc}{\lambda }$

$=6\times {10}^{-16}J$