An Inductance L, Resistance R, and Ideal Battery of Emf $\varepsilon$

Multiple Choice

An inductance L, resistance R, and ideal battery of emf $\varepsilon$ are wired in series. A switch in the circuit is closed at time 0, at which time the current is zero. At any later time t the current i is given by:

A) ( $\varepsilon$ /R) (1 - e^-Lt/R)
B) ( $\varepsilon$ /R) e^-Lt/R
C) ( $\varepsilon$ /R) (1 + e^-Rt/L)
D) ( $\varepsilon$ /R) e^-Rt/L
E) ( $\varepsilon$ /R) (1 - e^-Rt/L)