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A wire of cross-sectional area A forms t...

A wire of cross-sectional area A forms three sides of a square and is free to rotate about axis OO'. If the structure is deflected by an angle `theta` from the vertical when current i is passed through it in a magnetic field B acting vertically upward and density of the wire is `rho`, then the value of `theta` is given by

A

`(2Arhog)/(iB)=cot theta`

B

`(2Arhog)/(iB)=tan theta`

C

`(Arhog)/(iB)=sin theta`

D

`(Arhog)/(2iB)=cos theta`

Text Solution

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Magnetic torque is balanced by torque due to gravity.
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