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JEE Main2018PhysicsElectromagnetic InductionActual

A coil of cross-sectional 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:

Options

  1. A3 2 n B A ω
  2. B3 n B A ω
  3. Cn B A ω
  4. D1 2 n B A ω

Correct answer

C. n B A ω

Step-by-step solution

Magnetic flux through a coil of area A of n turns at an angle θ to the magnetic field of magnitude B is, φ = n B A   c o s θ = n B A c o s ω t . The induced emf, ε = d ϕ d t = n B A ω sin ⁡ ω t . Since, the maximum value of the sine function is 1 , ε m a x = n B A ω

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