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NEET2019PhysicsDual Nature of MatterActual

Assertion : A photon has no rest mass, yet it carries definite momentum. Reason : Momentum of photon is due to its energy and hence its equivalent mass.

Options

  1. AIf both assertion and reason are true and reason is the correct explanation of assertion.
  2. BIf both assertion and reason are true but reason is not the correct explanation of assertion.
  3. CIf assertion is true but reason is false.
  4. DIf both assertion and reason are false.

Correct answer

A. If both assertion and reason are true and reason is the correct explanation of assertion.

Step-by-step solution

Equivalent mass of photon ( m ) is given from equation E=m c^2=h v m= h v c^2 where E is energy, m is mass, c is speed of light, h is Planck's constant, v is frequency. Momentum of photon = h v c^2 c= h v c

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