Physics · Refraction of light at plane and spherical surfaces, thin lens formula and lens maker formula

Assertion Assertion: When a light wave travels from a rarer to a denser medium,

Assertion Assertion: When a light wave travels from a rarer to a denser medium, its speed decreases. The decrease in speed imply a reduction in energy carried by the light wave. Reason Reason: The energy of a wave is inversely proportional to velocity of wave

  • A. If both assertion and reason are true and reason is the correct explanation of assertion
  • B. If both assertion and reason are true and reason is not the correct explanation of assertion.
  • C. If assertion is true but reason is false
  • D. If both assertion and reason are false

Step-by-step solution

The assertion is false because the energy of a light wave (or photon) depends on its frequency, which remains constant when transitioning between media; the speed decrease does not imply energy reduction. The reason is also false because the energy of a wave is not universally inversely proportional to its velocity; for electromagnetic waves, energy is proportional to frequency, not inversely proportional to speed.
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