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If p represents radiation pressure, C represents the speed of light and q represents radiation energy striking a unit area per second, then non-zero integers a , b and c are such that p a q b C c is dimensionless, then

Options

  1. Aa = 1 , b = 1 , c = - 1
  2. Ba = 1 , b = - 1 , c = 1
  3. Ca = - 1 , b = 1 , c = 1
  4. Da = 1 , b = 1 , c = 1

Correct answer

B. a = 1 , b = - 1 , c = 1

Step-by-step solution

Here, M 0 L 0 T 0 = M L - 1 T - 2 a M T - 3 b L T - 1 c Or M 0 L 0 T 0 = [ M a + b L - a + c T - 2 a - 3 b - c ] Comparing powers of M , L and T , we get a + b = 0 , - a + c = 0 , - 2 a - 3 b = 0 Solving a = 1 , b = - 1 , c = 1

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