MCQ
The equation $E = pc$ is valid:
- AFor an electron as well as for a photon.
- BFor an electron but not for a photon.
- ✓For a photon but not for an electron.
- DNeither for an electron nor for a photon.
✓
Answer
Correct option: C.
For a photon but not for an electron.
The equation $E = pc$ is valid for a particle with zero rest mass. The rest mass of a photon is zero, but the rest mass of an electron is not zero. So, the equation will be valid for photon, and not electron.
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