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Electrostatics

Q.)

Three point charges, which initially are infinitely far apart are placed at the corners of an equilateral triangle with sides d. Two of the point charges are identical and have charge q. If zero net work is required to place the three charges at the corners of the triangle, what must be the value of the third charge be?

Ans. -q/2

Profile image of Abhisek Roy
14 Years agoGrade
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3 Answers

Profile image of Chetan Mandayam Nayakar
ApprovedApproved Tutor Answer14 Years ago

let k=4*pi*ε0

let third charge be Q

(1/k)((q2/d)+ (2Qq/d))=0

Profile image of DHRUBA JYOTI ROY KARMAKAR
ApprovedApproved Tutor Answer14 Years ago

let,the charge on third charge be Q...

so,calculate the energy of the third charge and equate it to zero

it will give you the charge of d third charge to be -q/2

Profile image of Abhisek Roy
13 Years ago

thanks wellwisher