A conducting rod of length L is hanging from ceiling with help of two light metallic threads as shown. There is some potential difference between A and D so that some current flows in the rod. When displaced perpendicular to plane of diagram slightly, the system oscillates with time period T. Now magnetic field B perpendicular to plane of diagram is switched on. The time period of oscillation now becomes 2 T . The magnitude of current flowing through rod is. (The magnetic field cuts through the rod only and not the threads)
Physics · Magnetic effect of current
A conducting rod of length L is hanging from ceiling with help of two light metallic threads as shown. There is some potential difference between A and D so that some current flows in the rod. When displaced perpendicular to plane of diagram slightly, the system oscillates with time period T. Now magnetic field B perpendicular to plane of diagram is switched on. The time period of oscillation now becomes 2 T . The magnitude of current flowing through rod is. (The magnetic field cuts through the rod only and not the threads)
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