Question

A battery of e.m.f. $E$ is connected with series $L-R$ circuit as shown in circuit. At $t=0$ switch $S$ is closed, If $e$ denotes the induced e.m.f. across the inductor and $i$ the current in the circuit at any time $t$ , then which of the following graphs shows the variation of $e$ with $i$ ?

• A.
• B.
• C.
• D.

Answer 1

Answer: (A)

The potential difference across the inductor is $e=E-iR$
Hence the plot of e versus i is a straight line with negative slope.