Question

In photoelectric effect, stopping potential for a light of frequency $n_1$ is $V_1$. If light is replaced by another having a frequency $n _2$ then its stopping potential will be

• A. $V _1-\frac{ h }{ e }\left( n _2- n _1\right)$
• B. $V _1+\frac{ h }{ e }\left( n _2+ n _1\right)$
• C. $V _1+\frac{ h }{ e }\left( n _2-2 n _1\right)$
• D. $V _1+\frac{ h }{ e }\left( n _2- n _1\right)$

Answer 1

Answer: (D)

$W _0= h v _1- e V _1$
$= h v _2- eV _2$
$e V_2=h\left(v_2-v_1\right)+e V_1$
$V _2=\frac{ h \left( n _2- n _1\right)}{ e }+ V _1$