Question

Electromagnetic radiation falls on a metallic body whose work function is $2eV$. For particular radiation of frequency $\nu$, the maximum kinetic energy of the photoelectron is found to be $4eV$. Find the maximum kinetic energy (in eV) of photoelectron for the radiation of $\frac{5\nu }{3}.$

• A. $8$
• B. $6$
• C. $16$
• D. $12$

Answer 1

The correct option is A $8$

Electromagnetic radiation falls on a metallic body whose work function is 2eV.
$h\nu =\varphi +K{E}_{max}\Rightarrow h\nu =2+4$
$\Rightarrow h\nu =6eV$

Again, $h\left(\frac{5\nu }{3}\right)=2+K{E}_{max}$

$\frac{5}{3}\times 6=2+K{E}_{max}$

$K{E}_{max}=8eV$

So, the answer is option (A).