JEE Mains · Physics · STD 12 - 2. Electric potential and capacitance
A parallel plate capacitor was made with two rectangular plates, each with a length of \(l=3 \mathrm{~cm}\) and breath of \(\mathrm{b}=1 \mathrm{~cm}\). The distance between the plates is \(3 \mu \mathrm{~m}\). Out of the following, which are the ways to increase the capacitance by a factor of 10 ?
A. \(l=30 \mathrm{~cm}, \mathrm{~b}=1 \mathrm{~cm}, \mathrm{~d}=1 \mu \mathrm{~m}\)
B. \(l=3 \mathrm{~cm}, \mathrm{~b}=1 \mathrm{~cm}, \mathrm{~d}=30 \mu \mathrm{~m}\)
C. \(l=6 \mathrm{~cm}, \mathrm{~b}=5 \mathrm{~cm}, \mathrm{~d}=3 \mu \mathrm{~m}\)
D. \(l=1 \mathrm{~cm}, \mathrm{~b}=1 \mathrm{~cm}, \mathrm{~d}=10 \mu \mathrm{~m}\)
E. \(l=5 \mathrm{~cm}, \mathrm{~b}=2 \mathrm{~cm}, \mathrm{~d}=1 \mu \mathrm{~m}\)
Choose the correct answer from the options given below:
- A A only
- B C only
- C B and D only
- D \(C\) and \(E\) only
Answer & Solution
Correct Answer
(D) \(C\) and \(E\) only
Step-by-step Solution
Detailed explanation
We know \(C=\frac{A \varepsilon_0}{d}\) \(=\frac{b \ell \varepsilon_0}{d}\) So to increase the capacitance by 10 factor \(\left(\frac{A}{d}\right)\) has to increase by 10 fator. For option (A)…
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