Match List-I with List-II.
| List-I | List-II |
|---|---|
| (A) Magnetic field \(B\) | (I) \([\mathrm{L^{-1}\,A}]\) |
| (B) Permeability of free space \(\mu_0\) | (II) \([\mathrm{M\,L^{2}\,T^{-2}\,A^{-1}}]\) |
| (C) Magnetic flux \(\phi_B\) | (III) \([\mathrm{M\,T^{-2}\,A^{-1}}]\) |
| (D) Magnetisation \(M\) | (IV) \([\mathrm{M\,L\,T^{-2}\,A^{-2}}]\) |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → (A)-(III), (B)-(IV), (C)-(II), (D)-(I)
(A) Magnetic field \( B \) — This matches (III) \( [\mathrm{M\,T^{-2}\,A^{-1}}] \). From \( F=qvB \), \( B=F/qv \), which gives \( [\mathrm{M\,L\,T^{-2}}]/([\mathrm{A\,T}][\mathrm{L\,T^{-1}}]) \).
(B) Permeability of free space \( \mu_0 \) — This matches (IV) \( [\mathrm{M\,L\,T^{-2}\,A^{-2}}] \). From \( B=\mu_0 nI \), \( \mu_0=B/nI \). Dividing \( [\mathrm{M\,T^{-2}\,A^{-1}}] \) by \( [\mathrm{L^{-1}\,A}] \) gives this result.
(C) Magnetic flux \( \phi_B \) — This matches (II) \( [\mathrm{M\,L^{2}\,T^{-2}\,A^{-1}}] \). Flux is field times area, so the dimensions of \( B \) are multiplied by \( [\mathrm{L^{2}}] \).
(D) Magnetisation \( M \) — This matches (I) \( [\mathrm{L^{-1}\,A}] \). It is magnetic moment per unit volume, \( [\mathrm{L^{2}\,A}]/[\mathrm{L^{3}}] \).
NCERT (2026-27):
Magnetisation and Magnetic Intensity – “… M is a vector with dimensions L–1 A and is measured in a units of A m–1.”
Summary
