JEE Advanced Model Paper 9 with solutions for online practice

A metal rod OA of mass ‘m’ and length ‘r’ kept rotating with constant angular speed ‘w’ ina vertical plane about a horizontal axis at the O. The free end A is arranged to slide withoutfriction along a fixed conducting circular ring in the same plane as that of rotations. Auniform and constant magnetic induction

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B

is applied perpendicular and into the plane ofrotation as shown in fig. An indicator ‘L’ and an external resistance R are connectedthrough a switch ‘S’ between the point ‘O’ and a point ‘C’ on the ring and the rod. Initially,the switch is open