Question

The work function of a metal is $5eV$. What is the kinetic energy of the photoelectron ejected from the metal surface if the energy of the incident radiation is $6.2eV$?

$[eV=1.6\times {10}^{-19}]$.

• A. $6.626\times {10}^{-19}J$
• B. $8.10\times {10}^{-19}J$
• C. $1.92\times {10}^{-18}J$
• D. $8.01\times {10}^{-18}J$
• E. $1.92\times {10}^{-19}J$

Answer 1

The correct option is E $1.92\times {10}^{-19}J$

Work function $\left(W\right)=h{v}_0=5eV$

Energy of incident radiation,
$hv=6.2eV$

The kinetic energy of photoelectron:

$=hv-W$

$=6.2-5$

$=1.2eV$

$=1.2\times 1.6\times {10}^{-19}J$

$=1.92\times {10}^{-19}J$