Q. The frequency of a photon having energy 100eV is (Take$\ h = 6.67 \times 10^{- 34}$ Js, $1$ eV =$1.6 \times 10^{- 19}$ J)
A) $2.4 \times 10^{- 16}$
B) $2.4 \times 10^{16}$
C) $2.4 \times 10^{17}$
D) 10.54$\times 10^{16}$
Explanation
(b) Given, $E = 100\ eV = 100 \times 1.6 \times 10^{- 19}$J
and $h = 6.662 \times 10^{- 34}$J
E= hv
$\ v = \frac{E}{h} = \frac{100 \times 1.6 \times 10^{- 19}}{6.662 \times 10^{- 34}}$
$= \ 0.24 \times 10^{17} = 2.4 \times 10^{16}\ Hz$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.