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NEET2002PhysicsWave OpticsActual

Assertion : Thin films such a soap bubble or a thin layer of oil on water show beautiful colours when illuminated by white light. Reason : It happens due to the interference of light reflected from the upper surface of the thin film.

Options

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

Correct answer

C. If the assertion is true but the reason is false.

Step-by-step solution

The beautiful colours are seen on account of interference of light reflected from the upper and the lower surfaces of the thin film. As conditions for constructive and destructive interference depend upon the wavelength of light, therefore coloured interference fringes are observed.

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