NEET2017PhysicsUnits and DimensionsActual
A physical quantity of the dimensions of length that can be formed out of c ,   G and e 2 4 π ε 0 , where [ c is velocity of light, G is universal constant of gravitation, e is charge & ε 0 is permittivity of free space]:
Options
- A1 c 2 G e 2 4 π ε 0 1 2
- Bc 2 G e 2 4 π ε 0 1 2
- C1 c 2 e 2 G 4 π ε 0 1 2
- D1 c G e 2 4 π ε 0
Correct answer
A. 1 c 2 G e 2 4 π ε 0 1 2
Step-by-step solution
Let e 2 4 π ε 0 = A = M L 3 T - 2 L = C x G y A z [ L ] = L T - 1 x M - 1 L 3 T - 2 y M L 3 T - 2 z - y + z = 0 ⇒ y = z ......(i) x + 3 y + 3 z = 1 ......(ii) - x - 4 z = 0 ......(iii) From (i), (ii) and (iii) z = y = 1 2 , x = - 2