Q. Calculate the energy of a photon with momentum $3.3 \times 10^{- 13}\ kg$-$ms^{- 1}$, given Planck’s constant to be $6.6 \times 10^{- 34}$ Js
A) $7.3 \times 10^{4}\ J$
B) $9.9 \times 10^{- 5}\ J$
C) $1.3 \times 10^{5}\ J$
D) $8.1 \times 10^{3}\ J$
Explanation
(b) Given $E/c\ = 3.3 \times 10^{- 13}kg\ ms^{- 1};$
So, $E = 3.3 \times 10^{- 13} \times c = 3.3 \times 10^{- 13} \times 3 \times 10^{8}$
$= 9.9 \times 10^{- 5}$ J
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.