JEE Mains · Physics · STD 12 - 2. Electric potential and capacitance
Three small identical bubbles of water having same charge on each coalesce to form a bigger bubble. Then the ratio of the potentials on one initial bubble and that on the resultant bigger bubble is:
- A \( 1:3^{1/3} \)
- B \( 1:2^{2/3} \)
- C \( 3^{2/3}: 1 \)
- D \( 1:3^{2/3} \)
Answer & Solution
Correct Answer
(D) \( 1:3^{2/3} \)
Step-by-step Solution
Detailed explanation
Using volume conservation \( 3(\frac{4}{3}\pi r^{3})=(\frac{4}{3}\pi R^{3}) \) \( R=3^{1/3}r \) \( \frac{V_{i}}{V_{f}}=\frac{\frac{kq}{r}}{\frac{k3q}{R}}=\frac{R}{3r}=\frac{3^{1/3}r}{3r}=\frac{1}{3^{2/3}} \)
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