Question

The formula of kinetic mass of photon is? Where h is Planck's constant, v is frequency of the photon and c is its speed.

• A. $\frac{hv}{c}$
• B. $\frac{hv}{c^2}$
• C. $\frac{hc}{v}$
• D. $\frac{c^2}{hv}$

Answer 1

Answer: (B)

$\frac{hv}{c^2}$

Energy of photon having frequency $v$ is given by $E=hv$
Energy of photon can be written as $E=m_k{c}^2$
where $m_k$ is the kinetic mass of photon
$\therefore$ $m_k{c}^2=hv$
$⟹m_k=\frac{hv}{c^2}$