JEE Mains · Physics · STD 12 - 2. Electric potential and capacitance
A capacitor of \(10 \mu \mathrm{F}\) capacitance whose plates are separated by \(10 \mathrm{~mm}\) through air and each plate has area \(4 \mathrm{~cm}^2\) is now filled equally with two dielectric media of \(\mathrm{K}_1=2, \mathrm{~K}_2=3\) respectively as shown in figure. If new force between the plates is \(8 \mathrm{~N}\). The supply voltage is _______ \(\times 10^{-4}\)V.

- A \(50\)
- B \(93\)
- C \(60\)
- D \(30\)
Answer & Solution
Correct Answer
(B) \(93\)
Step-by-step Solution
Detailed explanation
\(\mathrm{C}_{\mathrm{eq}}=\mathrm{C}_1+\mathrm{C}_2\) \(\mathrm{C}_1=\frac{2 \epsilon_0 \mathrm{~A}}{2 \times \mathrm{d}}=10 \mu \mathrm{F}\) \(\mathrm{C}_2=\frac{3 \epsilon_0 \mathrm{~A}}{2 \mathrm{~d}}=15 \mu \mathrm{F}\) \(\mathrm{C}_{\mathrm{eq}}=25 \mu \mathrm{F}\) Now the…
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