Q 11-01-079JEE MainJEE Main 2025 (23 Jan, Shift 2)Easy
Match List-I with List-II.
**List-I**
(A) Permeability of free space
(B) Magnetic field
(C) Magnetic moment
(D) Torsional constant
**List-II**
(I) $[ML^2T^{-2}]$
(II) $[MT^{-2}A^{-1}]$
(III) $[MLT^{-2}A^{-2}]$
(IV) $[L^2A]$
Choose the correct answer from the options given below:
Answer: (B) (A)-(III), (B)-(II), (C)-(IV), (D)-(I)
- Magnetic field: $F = qvB \Rightarrow [B] = \dfrac{[MLT^{-2}]}{[AT][LT^{-1}]} = [MT^{-2}A^{-1}]$ (II).
- Permeability: $F/l = \dfrac{\mu_0I^2}{2\pi d} \Rightarrow [\mu_0] = [MLT^{-2}A^{-2}]$ (III).
- Magnetic moment: $m = IA \Rightarrow [L^2A]$ (IV).
- Torsional constant: $\tau = k\theta \Rightarrow [ML^2T^{-2}]$ (I).
(A)-(III), (B)-(II), (C)-(IV), (D)-(I).
Solution by Sreeraj P, M.Sc Physics