Alternating Current Question 7

Question 7 - 2024 (29 Jan Shift 2)

In the given figure, the charge stored in $6 \mu \mathrm{F}$ capacitor, when points $\mathrm{A}$ and $\mathrm{B}$ are joined by a connecting wire is $\mu \mathrm{C}$.

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Answer: (36)

Solution:

At steady state, capacitor behaves as an open circuit and current flows in circuit as shown in the diagram.

$\mathrm{R}_{\text {eq }}=9 \Omega$

$\mathrm{i}=\frac{9 \mathrm{~V}}{9 \Omega}=1 \mathrm{~A}$

$\Delta \mathrm{V}_{6 \Omega}=1 \times 6=6 \mathrm{~V}$

$\mathrm{V}_{\mathrm{A}}=3 \mathrm{~V}$

So, potential difference across $6 \mu \mathrm{F}$ is $6 \mathrm{~V}$.

Hence

$$ \begin{aligned} Q & =C \Delta V \ & =6 \times 6 \times 10^{-6} \mathrm{C} \ & =36 \mu \mathrm{C} \end{aligned} $$