# In the circuit show below, the key K is closed at t=0. T

Question:

In the circuit show below, the key $\mathrm{K}$ is closed at $\mathrm{t}=0$. The current through the battery is :

1. $\frac{V\left(R_{1}+R_{2}\right)}{R_{1} R_{2}}$ at $t=0$ and $\frac{V}{R_{2}}$ at $t=\infty$

2. $\frac{\mathrm{VR}_{1} \mathrm{R}_{2}}{\sqrt{\mathrm{R}_{1}^{2}+\mathrm{R}_{2}^{2}}}$ at $\mathrm{t}=0$ and $\frac{\mathrm{V}}{\mathrm{R}_{2}}$ at $\mathrm{t}=\infty$

3. $\frac{\mathrm{V}}{\mathrm{R}_{2}}$ at $\mathrm{t}=0$ and $\frac{\mathrm{V}\left(\mathrm{R}_{1}+\mathrm{R}_{2}\right)}{\mathrm{R}_{1} \mathrm{R}_{2}}$ at $\mathrm{t}=\infty$

4. $\frac{\mathrm{V}}{\mathrm{R}_{2}}$ at $\mathrm{t}=0$ and $\frac{\mathrm{VR}_{1} \mathrm{R}_{2}}{\sqrt{\mathrm{R}_{1}^{2}+\mathrm{R}_{2}^{2}}}$ at $\mathrm{t}=\infty$

Correct Option: , 3

Solution: