Self Inductance — Prelims Questions

A solenoid has 2000 turns wound over a length of $0.5,\text{m}$ and has a cross-sectional area of $2 \times 10^{-4},\text{m}^2$. If the solenoid is air-cored, what is its self-inductance? (Given: $mu_0 = 4pi \times 10^{-7},\text{T m/A}$)

An inductor of $50,\text{mH}$ has a current changing at a rate of $200,\text{A/s}$. What is the magnitude of the induced EMF across the inductor?

An inductor of self-inductance $2,\text{H}$ stores $100,\text{J}$ of energy. What is the current flowing through it?

Which of the following factors does NOT affect the self-inductance of a solenoid?

When the current in an inductor is decreasing, the direction of the induced EMF will be:

An air-cored solenoid has a self-inductance $L_0$. If a soft iron core (relative permeability $mu_r = 500$) is inserted into the solenoid, its new self-inductance $L$ will be: