Column - I gives certain physical terms associated with flow of current through a metallic conductor.
Column - II gives some mathematical relations involving electrical quantities.
Match Column - I and Column - II with appropriate relations.
| |
Column - I | |
Column - II |
| (A) | Drift Velocity | (P) |
|
| (B) | Electrical Resistivity | (Q) | neνd |
| (C) | Relaxation Period | (R) |
|
| (D) | Current Density | (S) |
|
Correct Answer :
(A)-(R), (B)-(S), (C)-(P), (D)-(Q)
Solution :
To match the physical terms associated with the flow of current in Column-I with their appropriate mathematical relations in Column-II, we analyze each term step-by-step:
1. Drift Velocity (A):
When an electric field is applied across a conductor, the free electrons experience an electric force , leading to an acceleration , where is the charge and is the mass of an electron. The average velocity acquired by these electrons between successive collisions is called the drift velocity (), given by:
where is the relaxation period.
Therefore, (A) matches with (R).
2. Electrical Resistivity (B):
According to Ohm's law in vector form, the relation between the electric field , current density , and electrical resistivity is:
Rearranging this formula gives the expression for resistivity:
Therefore, (B) matches with (S).
3. Relaxation Period (C):
The electrical resistivity is micro-scopically related to the relaxation period by the formula:
Rearranging this to solve for the relaxation period gives:
where is the number density of free electrons.
Therefore, (C) matches with (P).
4. Current Density (D):
Current density is the electric current per unit cross-sectional area. It is related to the drift velocity of the charge carriers by the relation:
Therefore, (D) matches with (Q).
Combining all the individual matches, we get:
(A)-(R), (B)-(S), (C)-(P), (D)-(Q)
Access expert-curated educational resources and study materials—completely free.
Create, conduct, and manage professional online assessments with Mindyard. Perfect for teachers and institutes.
Copyright © 2026 Mindyard. All Rights Reserved.