A physical quantity of the dimensions of length that can be formed out of c, G and e24 0 is [c is velocity of light, G is the universal constant of gravitation and e is charge]
- c2 [G e24 0 ]1/2
- 1c2 [ e2G 4 0 ]1/2
- 1cG e24 0
- 1c2 [G e24 0 ]1/2
Answer
(4) 1c2 [G e24 0 ]1/2
Solution
[ e24 0 ] = [F r2] = [ML3T-2], [G] = [M-1L3T-2], [c] = [LT-1]
Let L = cx Gy ( e24 0 )z
[L] = [LT-1]x [M-1L3T-2]y [ML3T-2]z
M: -y + z = 0; L: x + 3y + 3z = 1; T: -x - 2y - 2z = 0
y = z, x = -4y
-4y + 6y = 1 y = z = 12, x = -2
Length = 1c2 [G e24 0 ]1/2
Answer: (4)