MCQ
Three charged concentric nonconducting shells are given as shown in figure. Find the potential at point $A$
- A$\frac{{5kQ}}{R}$
- ✓$\frac{{4kQ}}{R}$
- C$\frac{{3kQ}}{R}$
- D$\frac{{2kQ}}{R}$
✓
Answer
Correct option: B.
$\frac{{4kQ}}{R}$
b
$\mathrm{V}_{\mathrm{A}}=\frac{\mathrm{kQ}}{\mathrm{R}}+\mathrm{k} \frac{2 \mathrm{Q}}{2 \mathrm{R}}+\mathrm{k} \frac{8 \mathrm{Q}}{4 \mathrm{R}}=\frac{4 \mathrm{k} Q}{\mathrm{R}}$
$\mathrm{V}_{\mathrm{A}}=\frac{\mathrm{kQ}}{\mathrm{R}}+\mathrm{k} \frac{2 \mathrm{Q}}{2 \mathrm{R}}+\mathrm{k} \frac{8 \mathrm{Q}}{4 \mathrm{R}}=\frac{4 \mathrm{k} Q}{\mathrm{R}}$
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