n=2l1μT;I=1m T=10Kg wt. =10×10=100 N μ=9.8 g/m=9.8×10−3 kg/mn=50hz
JEE Main 2003 — Physics Electromagnetism
A metal wire of linear mass density of 9.8 g/m is stretched with a tension of 10 kg-wt between two rigid supports 1 metre apart. The wire passes at its middle point between the poles of a permanent magnet, and it vibrates in resonance when carrying an alternating current of frequency n. The frequency n of the alternating source is
Held on 30 Apr 2003 · Verified 6 Jul 2026.
50 Hz
100 Hz
200 Hz
25 Hz
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