What is the stopping potential, when a metal surface with work function $1.2 \mathrm{eV}$ is illuminated with light of energy $3 \mathrm{eV}$ ?A) $2V$B)$1 \cdot 2 \mathrm{~V}$C)$1 \cdot 4 \mathrm{~V}$D)$1.8 \mathrm{~V}$

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What is the stopping potential, when a metal surface with work function $1.2 \mathrm{eV}$ is illuminated with light of energy $3 \mathrm{eV}$ ?
A) $2V$
B) $1 \cdot 2 \mathrm{~V}$
C) $1 \cdot 4 \mathrm{~V}$
D) $1.8 \mathrm{~V}$

Physics

What is the stopping potential, when a metal surface with work function $1.2 \mathrm{eV}$ is illuminated with light of energy $3 \mathrm{eV}$ ?
A) $2V$
B) $1 \cdot 2 \mathrm{~V}$
C) $1 \cdot 4 \mathrm{~V}$
D) $1.8 \mathrm{~V}$

Correct option is D.

$\begin{array}{l} e V s=E-W_{0} \\ \therefore V_{s}=\frac{E}{e}-\frac{W_{0}}{e}=\frac{3 e}{e}-\frac{1.2 e V}{e}=1.8 V \end{array}$

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