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Question
Charges (+q) and (–q) are placed at points A and B respectively which are a distance 2L apart. C is the midpoint between A and B. What is the work done in moving a charge +Q along the semicircle CRD?
Solution
Vc = 0,
VD = `1/(4piepsi_0)[q/(3L) - q/L] = (-q)/(6piepsi_0L)`
W = Q[VD - Vc] = `(-Qq)/(6piepsi_0L)`
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