Match the LIST-I with LIST-II
| LIST-I | LIST-II | ||
|---|---|---|---|
| (Physical quantity) | (Unit) | ||
| A. | Electric potential | I. | \( \mathrm{m^{2}\ V^{-1}\ s^{-1}} \) |
| B. | Resistivity | II. | \( \mathrm{V\ m^{-1}} \) |
| C. | Mobility | III. | \( \mathrm{V\ m\ A^{-1}} \) |
| D. | Electric field | IV. | \( \mathrm{J\ C^{-1}} \) |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → A-IV, B-III, C-I, D-II
Each unit follows from the defining relation of the quantity.
(A) Electric potential — this matches (IV) J C−1. Potential is work done per unit charge.
\( \displaystyle V = \frac{W}{q} \)
(B) Resistivity — this matches (III) V m A−1. From \( R = \rho l/A \), resistivity is measured in ohm metre, and \( 1\,\Omega = 1\,\mathrm{V\,A^{-1}} \).
\( \displaystyle \rho = \frac{RA}{l} \)
(C) Mobility — this matches (I) m2 V−1 s−1. Mobility is the drift speed per unit field, so its unit is \( (\mathrm{m\,s^{-1}})/(\mathrm{V\,m^{-1}}) \).
\( \displaystyle \mu = \frac{v_{d}}{E} \)
(D) Electric field — this matches (II) V m−1. Field is the potential gradient.
\( \displaystyle E = \frac{V}{d} \)