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JEE Main202127 Aug 2021Evening ShiftPhysicsUnits and DimensionsActual

If force (F), length (L) and time (T) are taken as the fundamental quantities. Then what will be the dimension of density:

Options

  1. AFL - 4   T 2
  2. BFL - 3   T 3
  3. CFL - 3   T 2
  4. DFL - 5   T 2

Correct answer

A. FL - 4   T 2

Step-by-step solution

d ∝ F a L b T c M L - 3 = M L T - 2 a L b T   c = M a L a + b T - 2 a + c comparing : a = 1 ......(i) a + b = - 3 ....(ii) - 2   a + c = 0 .......(iii) c = 2    ;    b = - 4    ;    ∴    [ d ] = FL - 4   T 2

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