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JEE Main202125 Feb 2021Evening ShiftPhysicsUnits and DimensionsActual

If e is the electronic charge, c is the speed of light in free space and h is Planck's constant, the quantity 1 4 π ε 0 e 2 h c has dimensions of :

Options

  1. AMLT 0
  2. BM 0   L 0   T 0
  3. CMLT - 1
  4. DLC - 1

Correct answer

B. M 0   L 0   T 0

Step-by-step solution

F = 1 4 π ϵ 0 e 2 r 2 E = h c λ e 2 4 π ε 0 × 1 h c = F r 2 E λ = M 0   L 0   T 0

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