Question 168: AC fundamentals

Question

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

Accepted Answer

At $t=0,$ no current will flow through $L$ and ${R_1}$
$	herefore$ Current through battery $ = {V \over {{R_2}}}$
At $t = \infty ,$
effective resistance, ${{\mathop{m R}
olimits} _{eff}} = {{{R_1}{R_2}} \over {{R_1} + {R_2}}}$
$	herefore$ Current through battery $ = {V \over {{{\mathop{m R}
olimits} _{eff}}}} = {{V\left( {{R_1} + {R_2}} ight)} \over {{R_1}{R_2}}}$

Answer

${{V{R_1}{R_2}} \over {\sqrt {R_1^2 + R_2^2} }}$ at $t=0$ and ${V \over {{R_2}}}$ at $t = \infty $

Answer

${V \over {{R_2}}}$ at $\,t = 0$ and ${{V\left( {{R_1} + {R_2}} \right)} \over {{R_1}{R_2}}}$ at $t = \infty $

Answer

${V \over {{R_2}}}$ at $\,t = 0$  and ${{V{R_1}{R_2}} \over {\sqrt {R_1^2 + R_2^2} }}$ at $t = \infty $

Answer

${{V\left( {{R_1} + {R_2}} \right)} \over {{R_1}{R_2}}}$ at $t=0$ and ${V \over {{R_2}}}$ at $t = \infty $

AC fundamentals

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

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