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A metallic conductor of length 1 m rotates in a vertical plane parallel to east-west direction about one of its end with angular velocity 5 rad s⁻¹. If the horizontal component of earth's magnetic field is 0.2 × 10⁻⁴ T, then emf induced between the two ends of the conductor is:
- 5 μV
- 50 μV
- 5 mV
- 50 mV
Correct answer: 50 μV
Solution
The induced emf in a rotating conductor can be calculated using the formula emf = B * L * v, where B is the magnetic field strength, L is the length of the conductor, and v is the linear velocity at the end of the conductor. In this case, the linear velocity can be derived from the angular velocity, leading to an induced emf of 50 μV.
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