NEET-XII-Physics
42: Photoelectric Effect and Wave Particle Duality
- #6Should the energy of a photon be called its kinetic energy or its internal energy?Ans : Relativistic equation of energy:
`` {E}^{2}={p}^{2}{c}^{2}+{m}^{2}{c}^{4}...\left(1\right)``
Here, p2c2 = kinetic energy of photon
m02c4 = internal energy of photon
We know photons have zero rest mass. Therefore, m0 = 0.
Substituting the value of m0 = 0 in equation (1), we get:
`` E=pc``
Thus, the energy of a photon should be called its kinetic energy.
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