Electrostatics Question 528
Question: $ n $ identical condensers are joined in parallel and are charged to potential$ V $ . Now they are separated and joined in series. Then the total energy and potential difference of the combination will be [MP PET 1993]
Options:
A) Energy and potential difference remain same
B) Energy remains same and potential difference is $ nV $
C) Energy increases $ n $ times and potential difference is $ nV $
D) Energy increases $ n $ times and potential difference remains same
Show Answer
Answer:
Correct Answer: B
Solution:
According to energy conservation, energy remains the same therefore $ U _{parallel}=U _{series} $
therefore $ \frac{1}{2}(nC)V^{2}=\frac{1}{2}( \frac{C}{n} )V{{’}^{2}} $
therefore V’ = nV ($ V’ $ = potential difference across series combination)
