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Derivean expression forpotentialenergyof electric - di-poleplacedin a n uniformelectricfield . |
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Answer» SOLUTION :We knowthe torfque on an electric dipoleplacedin an electric FIELD , ` t = pEsintheta ` Bydefinitionwork done by torque on thedipole ` dW = tdtheta ` ` dW = pEsintheta .dtheta ` Net workdoneto movefrom ` theta_(1) " to"theta_(2)`is givenby ` W = int dW = int_(theta_(1))^(theta_(2)) p E sin theta d theta ` `W = -pE ( cos theta)_(theta_(2))^(theta_(1))` ` W = -pE ( cos theta_(2) - cos theta_(1))` Taking ` theta_(1) = 90^(@)and theta_(2) = theta `we can write . ` W = - pE cos theta ` ` W = BARP. vecE` This work done willbe storedin the FORM of potentialenergy. `i.e,P.E = - VECP. vecE` |
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