MCQ
The equation E = pc is valid:
  • A
    For an electron as well as for a photon.
  • B
    For an electron but not for a photon.
  • For a photon but not for an electron.
  • D
    Neither 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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