Q. The energy of a photon of light of wavelength $450\ nm$ is
A) $4.4 \times 10^{- 19}J$
B) $2.5 \times 10^{- 19}J$
C) $1.25 \times 10^{- 17}J$
D) $2.5 \times 10^{- 17}J$
Explanation
(a) $E = \frac{hc}{\lambda} = \frac{6.62 \times 10^{- 34} \times 3 \times 10^{8}}{450 \times 10^{- 9}} = 4.4 \times 10^{- 19}J$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.