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Light of uniform intensity impinges perpendicularly on a totally reflecting surface. If the area of the surface is halved, the radiation force on it will become

Options

  1. Adouble
  2. Bhalf
  3. Cfour times
  4. Done fourth

Correct answer

B. half

Step-by-step solution

We know that force, F = p t = 2 I A C Here, I = Intensity of light falling on the surface C = Speed of light A= Area of surface. If A is halved, then F = 2 I A 2 C = I A C Thus, Force becomes half.

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