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JEE Main201815 Apr 2018Evening ShiftPhysicsUnits and DimensionsActual

The characteristic distance at which quantum gravitational effects are significant, the Planck length, can be determined from a suitable combination of the fundamental physical constants G , h and c . Which of the following correctly gives the Planck length?

Options

  1. AG ^2 hc
  2. B( Gh c ^3 )^ 1 2
  3. CG ^ 1 2 ~h ^2 c
  4. DG (h^2 c ^3 .

Correct answer

B. ( Gh c ^3 )^ 1 2

Step-by-step solution

Plank length is a unit of length, aligned &l_p=1.616229 10⁻³⁵ ~m &l_p= h G c^3 aligned

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