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Question
A conducting square loop of side l and resistance R moves in its plane with a uniform velocity v perpendicular to one of its sides. A uniform and constant magnetic field Bexists along the perpendicular to the plane of the loop as shown in figure. The current induced in the loop is _____________ .
Options
Blv/R clockwise
Blv/R anticlockwise
2Blv/R anticlockwise
zero
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Solution
Zero
Figure (a) shows the square loop moving in its plane with a uniform velocity v.
Figure (b) shows the equivalent circuit.
The induced emf across ends AB and CD is given by
`E=Bvl`
On applying KVL in the equivalent circuit, we get
`E-E+iR=0`
`rArr i=0`
No current will be induced in the circuit due to zero potential difference between the closed ends.
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