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Question
The current generator Ig' shown in figure, sends a constant current i through the circuit. The wire ab has a length l and mass m and can slide on the smooth, horizontal rails connected to Ig. The entire system lies in a vertical magnetic field B. Find the velocity of the wire as a function of time.
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Solution
Because current i passes through the sliding wire, the magnetic force on the wire (F) is ilB.
Now,
Acceleration of the sliding wire, `a=(ilB)/m`
Velocity of the sliding wire, v = u + at
∵ u = 0
`therefore v = (ilBt)/m`
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