JEE Mains · Physics · STD 12 - Electric potential and capacitance
- JEE Mains 2020
- Hard
- MCQ
Two isolated conducting spheres \(S_{1}\) and \(S_{2}\) of radius \(\frac{2}{3} R\) and \(\frac{1}{3} R\) have \(12\, \mu C\) and \(-3\, \mu C\) charges, respectively, and are at a large distance from each other. They are now onnected by a conducting wire. A long time after this is done the charges on \(S_{1}\) and \(S_{2}\) are respectively
Pick an option to check your answer.
Answer & Solution
Correct Answer
(A) \(6\, \mu C\) and \(3\, \mu C\)
Step-by-step Solution
Detailed explanation
Now
\(Q _{1}+ Q _{2}= Q _{1}+ Q _{2}^{\prime}=12 \mu C -3 \mu C =9 \mu C\)
\(\& V_1=V_{2} \Rightarrow \frac{K Q_{1}^{\prime}}{\frac{2 R}{3}}=\frac{K Q_{2}^{\prime}}{\frac{R}{3}}\)
\(Q _{1}^{\prime}=2 Q _{2}^{\prime} \Rightarrow 2 Q _{2}^{\prime}+ Q _{2}^{\prime}=9 \mu C\)
\(\Rightarrow Q _{2}^{\prime}=3 \mu C\)
\(\ \quad Q_{1}^{\prime}=6 \mu C\)
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