Question

The mass of photon having wavelength $1\, nm$ is:

• A. $2.21 \times 10^{-35} kg$
• B. $2.21 \times 10^{-33} g$
• C. $2.21 \times 10^{-33} kg$
• D. $2.21 \times 10^{-26} kg$

Answer 1

Answer: (C)

$\lambda=\frac{h}{m c}$

$m=\frac{h}{\lambda c}$

$=\frac{6.626 \times 10^{-34}}{1 \times 10^{-9} \times 3 \times 10^{8}}$

$=2.21 \times 10^{-33} kg .$