Question

If the energy of photon is 10eV and work function is 5eV, then the value of stopping potential will be

• A. 15 V
• B. 5 V
• C. 2 V
• D. 50 V

Answer 1

Answer: (B)

5 V

Stopping potential ($V_o$) is given by

$V_o=\frac{W}{q}$ where $W$ is the work function and $q$ is the charge of an electron.

Given $W=10eV-5eV=5eV$. Also $q=e$

Hence $V_o=\frac{5eV}{e}=5V$

So, the answer is option (B).