JEE Mains · Physics · STD 12 - 2. Electric potential and capacitance
The space between the plates of a parallel-plate capacitor of capacitance C (without any dielectric) is now filled with three dielectric slabs of dielectric constants \(K _1=2, K_2=3\), and \(K _3=5\) (as shown in the figure). If new capacitance is \(\frac{ n }{3} C\) then the value of \(n\) is ___________.
- A 6
- B 7
- C 8
- D 9
Answer & Solution
Correct Answer
(C) 8
Step-by-step Solution
Detailed explanation
\(C _1=\frac{5 \in_0 A / 2}{d / 2}=\frac{5 \in_0 A}{ d }=5 C\) \(C _2=\frac{2 \in_0 A / 2}{d / 2}=\frac{2 \in_0 A}{ d }=2 C\) \(C _1 \& C _2\) in series. \(C^{\prime}=\frac{C_1 C_2}{C_1+C_2}=\frac{(5 C)(2 C)}{7 C}=\frac{10}{7} C\) \(C _3=\frac{3 \in_0 A / 2}{d / 2}=3 C\)…
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