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A rectangular wire-loop of width a is s...

A rectangular wire-loop of width a is suspended from the insulated pan of a spring blance as shown in A current I exists in the anticlockwise direction in the loop. A magnetic field B exists in the lower region.Find the change in the tension of the spring if the current in the loop is reversed.

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Force in the lower side of rectingular loop due to current I in magnetic fied B Initially when current is flowing in anticlockwise direction .
Then ` F= iab in right of a
when current is reversed the tension is
` F = iaB in left of a `
So , change in tension
` = iaB - (-iaB) = 2 iaB`
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HC VERMA-MAGNETIC FIELD-Exercises
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  2. A hypothetical magnetic field existing in a region is given by vecB= B...

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  4. A current loop of arbitrary shape lien in a uniform magnetic field B. ...

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  14. Shows a circular wire-loop of radius a m carrying a current I, placed ...

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  15. Suppose that the radius of cross section of the wire used in the previ...

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  16. The magnetic field existing in a region is given by vecB =B0(1+(x)/(l)...

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  17. A conducting wire of length l, lying normal to a magnetic field B, mo...

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  18. A currrent I is passed through a silver strip of width d and area of...

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  19. A particle having a charge of 2.0X10^(-8) C and a mass of 2.0X10^(-10...

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