JEE Mains · Physics · STD 12 - 2. Electric potential and capacitance
Two identical capacitors have same capacitance \(C\). One of them is charged to the potential \(\mathrm{V}\) and other to the potential \(2 \mathrm{~V}\). The negative ends of both are connected together. When the positive ends are also joined together, the decrease in energy of the combined system is _______.
- A \(\frac{1}{4} \mathrm{CV}^2\)
- B \(2 \mathrm{CV}^2\)
- C \(\frac{1}{2} \mathrm{CV}^2\)
- D \(\frac{3}{4} \mathrm{CV}^2\)
Answer & Solution
Correct Answer
(A) \(\frac{1}{4} \mathrm{CV}^2\)
Step-by-step Solution
Detailed explanation
\(\mathrm{V}_{\mathrm{C}}-\frac{\mathrm{q}_{\text {net }}}{\mathrm{C}_{\text {net }}}=\frac{\mathrm{CV}+2 \mathrm{CV}}{2 \mathrm{C}}\) \(\mathrm{V}_{\mathrm{C}}=\frac{3 \mathrm{~V}}{2}\) Loss of energy…
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