Energy Stored In An Inductor - Practice Questions & MCQ

Energy stored in an inductor (U)-

In building a steady current in the circuit, the source emf has to do work against of self-inductance of the coil and whatever energy
consumed for this work stored in the magnetic field of coil this energy called as magnetic potential energy (U) of the coil.

When an electric current i is flowing in an inductor, there is energy stored in the magnetic field. Considering a pure inductor L, the instantaneous power which must be supplied to initiate the current in the inductor is

The work done by the voltage source during a time interval  is

total work  done in establishing the final current  in the inductor

So Energy stored in the magnetic field of the inductor is given as

The energy density (u)/Energy per unit volume-

using 

for the solenoid field, we can write