Question

In the expression of current in the R-L circuit the transient part is?

(a) R/V

(b) (V/R)(-exp⁡((R/L)t))

(c) (V/R)(exp⁡((R/L)t))

(d) V/R

I had been asked this question in an international level competition.

Question is from DC Response of an R-L Circuit in portion Transients of Network Theory

Answer 1

Right choice is (b) (V/R)(-exp⁡((R/L)t))

Explanation: The expression of current in the R-L circuit has the transient part as

(V/R)(-exp⁡((R/L)t)). The transition period is defined as the time taken for the current to reach its final or steady state value from its initial value.