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A coil of cross-section area A having n turns is placed in a uniform magnetic field B. When it is rotated with an angular velocity ω, the maximum e.m.f. induced in the coil will be - [JEE-Main On line-2018]
- nBAω
- 3/2 nBAω
- 3nBAω
- 1/2 nBAω
Correct answer: nBAω
Solution
The induced e.m.f. in a coil rotating in a magnetic field is given by Faraday's law of electromagnetic induction, which states that the induced e.m.f. is proportional to the rate of change of magnetic flux. In this case, the maximum e.m.f. occurs when the coil is perpendicular to the magnetic field, leading to the formula nBAω, where n is the number of turns, A is the area, B is the magnetic field strength, and ω is the angular velocity.
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