Match List-I with List-II
| List-I | List-II |
| (A) Current | (I) Opposition to flow of current |
| (B) Resistance | (II) Rate of flow of charge |
| (C) Resistivity | (III) Work done per unit charge |
| (D) EMF | (IV) Resistance per unit length × unit cross-sectional area |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → (A) - (II), (B) - (I), (C) - (IV), (D) - (III)
Each item is a basic definition from current electricity.
(A) Current — this matches (II) Rate of flow of charge. Current is the charge crossing a section per unit time.
\( \displaystyle I = \frac{dq}{dt} \)
(B) Resistance — this matches (I) Opposition to flow of current. A conductor with a larger resistance allows less current for the same potential difference.
\( \displaystyle R = \frac{V}{I} \)
(C) Resistivity — this matches (IV) Resistance per unit length × unit cross-sectional area. It is the resistance of a conductor of unit length and unit cross-section, a property of the material.
\( \displaystyle \rho = \frac{R\,A}{l} \)
(D) EMF — this matches (III) Work done per unit charge. The emf is the work done by the source in moving a unit charge round the complete circuit.
\( \displaystyle \varepsilon = \frac{W}{q} \)