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A circular coil of radius 10 cm is placed in a uniform magnetic field of 3.0 × 10⁻⁵ T with its plane perpendicular to the field initially. It is rotated at constant angular speed about an axis along the diameter of the coil and perpendicular to magnetic field so that it undergoes half of rotation in 0.2s. The maximum value of emf induced in (μV) in the coil will be close to the integer _______.
- 15
- 10
- 20
- 25
Correct answer: 15
Solution
The induced emf in a rotating coil can be calculated using Faraday's law of electromagnetic induction, which states that the emf is proportional to the rate of change of magnetic flux. Given the coil's area and the uniform magnetic field, the maximum emf occurs when the coil is perpendicular to the field, and with the specified rotation speed, the calculated value rounds to 15 μV.
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