Question

A. The energy $E$ and momentum $p$ of a photon are related as $p=\frac{E}{c}$.

R. The photon behaves as a particle.

• A. $A$ and $R$ are both correct and $R$ is correct explanation of $A$
• B. $A$ and $R$ are correct but $R$ is not correct explanation of $A$
• C. $A$ is correct but $R$ is false
• D. Both $A$ and $R$ are false

Answer 1

Answer: (B)

$A$ and $R$ are correct but $R$ is not correct explanation of $A$

Assertion is correct and reason is too correct but it is not a correct explanation.
Suppose if a particle as kinetic energy $K$ then its velocity will be $\sqrt{\frac{K}{2m}}$ where m is mass of particle , then its momentum is mass times its velocity .

So photon is a particle will just not be sufficient to explain the assertion.

So, the answer is option (B).