WBJEE · Physics · Electrostatics
Consider two concentric conducting sphere of radii \(\mathrm{R}\) and \(2 \mathrm{R}\) respectively. The inner sphere is given a charge \(+\mathrm{Q}\). The other sphere is grounded. The potential at \(r=\frac{3 R}{2}\) is
- A \(\frac{1}{4 \pi \varepsilon_0} \frac{Q}{6 R}\)
- B 0
- C \(\frac{1}{4 \pi \varepsilon_0} \frac{2 Q}{3 R}\)
- D \(\frac{1}{4 \pi \varepsilon_0} \frac{Q}{R}\)
Answer & Solution
Correct Answer
(A) \(\frac{1}{4 \pi \varepsilon_0} \frac{Q}{6 R}\)
Step-by-step Solution
Detailed explanation
\(q \rightarrow\) Charge appearing on shell of radius \(2 R\) after earthing Calculating \(\mathrm{q} \quad \mathrm{V}_{\text {outer shell }}=\frac{\mathrm{KQ}}{2 \mathrm{R}}+\frac{\mathrm{Kq}}{2 \mathrm{R}}=0 \quad \mathrm{q}=-\mathrm{Q}\) Calculating potential at…
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