Question

The mass of photon having wavelength $1nm$ 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)

$\lambda =\frac{h}{mc}$

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

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

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