AP® Physics C: E&M - Circuits with Resistors and Inductors (LR Circuits) - MCQs
Questions
The circuit shown above consists of a battery of emf \(\varepsilon \) and internal resistance r, a resistor R, an inductor L, and a switch S, initially in position 1. After the current i in the inductor reaches its maximum value \(I_{\circ }\), S is switched instantaneously from position 1 to position 2 at time t = 0. Subsequent variation of i with t is best represented by which of the following graphs?
▶️Answer/Explanation
Ans: B
Question
An inductor and two resistors are connected to an ideal battery, as shown in the figure above. What is the time constant for the circuit?
(A) 0.22 μs
(B) 0.33 μs
(C) 0.67 μs
(D) 1.0 μs
(E) 72 μs
Answer/Explanation
Ans:D
Question
After the switch is closed in the circuit above, the current in the circuit is given by \(i=I(1-e^{-t/\varsigma })\) where Iand \(\varsigma \)are constants.
What is the value of I ?
(A) 0
(B) 0.001 A
(C) 0.80 A
(D) 1.0 A
(E) 4.0 A
Answer/Explanation
Ans:B