A 20 m long uniform copper wire held horizontally is allowed to fall under the gravity (g=10 m/s2) through a uniform horizontal magnetic field of 0.5 Gauss perpendicular to the length of the wire. The induced EMF across the wire when it travells a vertical distance of 200 m is ____ mV.
Held on 23 Jan 2026 · Verified 6 Jul 2026.
2010
0.210
20010
210
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