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JEE MAIN 2020
02-09-2020 S2
Question
A charge $Q$ is distributed over two concentric conducting thin spherical shells radii $r$ and $R(R>r)$. If the surface charge densities on the two shells are equal, the electric potential at the common centre is
Select the correct option:
A
$\frac{1}{4 \pi \varepsilon_0} \frac{(\mathrm{R}+\mathrm{r})}{\left(\mathrm{R}^2+\mathrm{r}^2\right)} \mathrm{Q}$
B
$\frac{1}{4 \pi \varepsilon_0} \frac{(\mathrm{R}+2 \mathrm{r}) \mathrm{Q}}{2\left(\mathrm{R}^2+\mathrm{r}^2\right)}$
C
$\frac{1}{4 \pi \varepsilon_0} \frac{(\mathrm{R}+\mathrm{r})}{2\left(\mathrm{R}^2+\mathrm{r}^2\right)} \mathrm{Q}$
D
$\frac{1}{4 \pi \varepsilon_0} \frac{(2 \mathrm{R}+\mathrm{r})}{\left(\mathrm{R}^2+\mathrm{r}^2\right)} \mathrm{Q}$
✓ Correct! Well done.
✗ Incorrect. Try again or view the solution.
Solution
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JEE Main
Physics
Medium
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