A constant electromotive force E volts is applied to a circuit containing a constant resistance R ohm in series with a constant inductance L henries. If the initial current is zero. What is the current in the circuit at any time t?

• A. ( frac{E}{R} left(1-e^{ frac{-Rt}{L}} right) )
• B. ( frac{E}{R} left(e^{ frac{Rt}{L}} right) )
• C. ( frac{E}{L} (1-e^{RLt}) )
• D. ( frac{E}{L} (e^{-RLt}) )