Won't back emf in an inductor induces an emf again?

Question

When an inductor is connected to a DC source, current starts passing through inductor. This generates magnetic field so flux associated with inductor changes. So a back emf is generated. As a result net emf decreases and so does current and magnetic field intensity. So magnetic flux change is there. Won't again an emf be induced in such a way to oppose the back emf? Thinking that all these happens in small time interval......

mike stone · Answer

Yes. That's why you need a differential equation
$$
L frac{dI}{dt}= V,
$$
whose solution (with $I=0$ at $t=0$)  is $I=Vt/L$.

Farcher · Answer

As a result net emf decreases and so does current  . . . .

This is not true, rather the rate of change of current decreases whilst the current continues to increase to an asymptotic value equal to the emf of the power supply divided by the resistance of the circuit.
In theory, the rate of change of current stays the same and the current just keeps increasing if there is no resistance in the circuit.

Won't back emf in an inductor induces an emf again?

2 Answers

Add your own answers!

Ask a Question