Q. Regarding self-inductance: A. The self-inductance of the coil depends on its geometry. B. Self-inductance does not depend on the permeability of the medium. C. Self-induced e.m.f. opposes any change in the current in a circuit. D. Self-inductance is electromagnetic analogue of mass in mechanics. E. Work needs to be done against self-induced e.m.f. in establishing the current. Choose the correct answer from the options given below:
A) A, B, C, E only
B) B, C, D, E only
C) A, C, D, E only
D) A, B, C, D only
Explanation
[Solution by Dr. Abubacker] $L=\mu N^2A/l$ depends on geometry and on the permeability, so A is true and B is false. Lenz's law gives C. $L$ plays the role of inertia (mass) for current, so D is true. Energy $\frac12LI^2$ is stored by working against the back emf, so E is true. Answer (3).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.