Question
Prove that an ideal inductor does not dissipate power in an a.c. circuit.
Or
Derive an expression for the self-inductance of a long air cored solenoid of length I and number of turns N.
Solution
The instantaneous EMF is given by E = E0 sin ωt
The instantaneous current in the inductor is given by I= I0 cos ωt
The instantaneous power in the inductor is given by P = EI
= E0 I0 cos ωt sin ωt
=
The average power over the complete cycle
Hence, an ideal inductor does not dissipate power.
The instantaneous current in the inductor is given by I= I0 cos ωt
The instantaneous power in the inductor is given by P = EI
= E0 I0 cos ωt sin ωt
=
The average power over the complete cycle
Hence, an ideal inductor does not dissipate power.
