A metallic wire is folded to form a square loop a side 'a'. It carries a current 'i' and is kept perpendicular to a uniform magnetic field. If the shape of the loop is changed from square to a circle withoul changing the length of the wire and current, the amount of work done in doing so is

A metallic wire is folded to form a square loop a side 'a'. It carries

1.	A metallic wire is folded to form a square loop a side 'a'. It carries a current 'i' and is kept perpendicular to a uniform magnetic field. If the shape of the loop is changed from square to a circle withoul changing the length of the wire and current, the amount of work done in doing so is
Answer» Solution :W = Find P.E - initial P.E `W=-M_(F)B-(-M_(i)B)` `W=iB(A_(i)-A_(f))W=iBa^(2)[1-4/pi]`

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A metallic wire is folded to form a square loop a side 'a'. It carries a current 'i' and is kept perpendicular to a uniform magnetic field. If the shape of the loop is changed from square to a circle withoul changing the length of the wire and current, the amount of work done in doing so is

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