JEE Main 2026 Jan 22 Shift 1, Physics Q19: Units And Dimensions

JEE Main2026Jan 22, Shift 1Physics

Match the LIST-I with LIST-II

Choose the correct answer from the options given below:

A
A-II, B-I, C-IV, D-III
B
A-I, B-IV, C-II, D-III
C
A-III, B-II, C-IV, D-I
D
A-II, B-IV, C-I, D-III

Solution

(A) Spring constant: from $F = k x$ , $[k] = [F] / [L] = M L T^{- 2} / L = M L^{0} T^{- 2}$ → (II).

(B) Thermal conductivity: from $\frac{d Q}{d t} = \frac{k A Δ T}{ℓ}$ , $[k] = \frac{[ Q / t ] [ ℓ ]}{[ A ] [ Δ T ]} = \frac{M L ^{2} T ^{- 3} \cdot L}{L ^{2} \cdot K} = M L T^{- 3} K^{- 1}$ → (IV).

(C) Boltzmann constant: from $P V = N k T$ , $[k] = \frac{[ P ] [ V ]}{[ T ]} = \frac{M L ^{- 1} T ^{- 2} \cdot L ^{3}}{K} = M L^{2} T^{- 2} K^{- 1}$ → (I).

(D) Inductive reactance ( $V / I$ ): $[X_{L}] = \frac{M L ^{2} T ^{- 3} A ^{- 1}}{A} = M L^{2} T^{- 3} A^{- 2}$ → (III).

So A-II, B-IV, C-I, D-III.

Concept behind this question

Units And DimensionsNotes, formulas and examples →

Practice more Physics

Concept-wise practice with instant solutions on Fundamenthol.

Start practicing →

JEE Main 2026 Jan 22 Shift 1, Physics Q19: Units And Dimensions

Concept behind this question

More previous year questions on Units And Dimensions

Practice more Physics