Explanation:
For series C - R circuit, the impedance $\text{Z}=\sqrt{\text{R}^2+\text{X}^2_\text{C}}$ where $\text{X}_\text{C}=\frac{\text{i}}{\omega\text{C}}$ and current $\text{I}=\frac{\text{V}}{\text{Z}}$
When the capacitor is filled by mica, the capacitance will be increased. If C increases, XC decreases, so the current will increase and
hence voltage across resistance increases and voltage across capacitor decreases. thus, Va > Vb
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(a) Torque is formed |
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(c) Both (a) and (b) are correct |
(d) None of these |
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(d) 
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(a) 25 D |
(b) – 25 D |
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(a) 1 μF |
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