Question

In the circuit shown below, the key K is closed at t = 0. The current through the battery is:

• A. $\frac{V{R}_1{R}_2}{\sqrt{R_1^2+R_2^2}}$ at $t=0$ and $\frac{V}{R_2}$ at $t=\infty$
• B. $\frac{V}{R_2}$ at $t=0$ and $\frac{V(R_1+R_2)}{R_1{R}_2}$ at $t=\infty$
• C. $\frac{V}{R_2}$ at $t=0$ and $\frac{V{R}_1{R}_2}{\sqrt{R_1^2+R_2^2}}$ at $t=\infty$
• D. $\frac{V(R_1+R_2)}{R_1{R}_2}$ at $t=0$ and $\frac{V}{R_2}$ at $t=\infty$

Answer 1

Answer: (B)

At $t=0$, inductor behaves like an infinite resistance