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Question
A rectangular conductor LMNO is placed in a uniform magnetic field of 0.5 T. The field is directed perpendicular to the plane of the conductor. When the arm MN of length of 20 cm is moved towards left with a velocity of 10 ms−1, calculate the emf induced in the arm. Given the resistance of the arm to be 5 Ω (assuming that other arms are of negligible resistance) find the value of the current in the arm.
Solution
Let ON be x at some instant.
The emf induced in the loop = e.
`e = (dphi)/dt = - (d(Blx))/dt =Bt (-dx/dt) = Blv = 0.5 xx 0.2 xx 10 = 1 V`
therefore Current in the arm, `I = e/R = 1/5 = 0.2 A`
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