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JEE Main20202 Sep 2020Morning ShiftPhysicsElectromagnetic InductionActual

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 coil and perpendicular to magnetic field so that it undergoes half of rotation in 0 . 2   s . The maximum value of EMF induced (in μV ) in the coil will be close to the int

Correct answer

15

Step-by-step solution

Flux as a function of time ϕ = B → · A → = A B cos ( ω t ) Emf induced, e = - d ϕ dt = AB ω sin ( ω t ) Max. value of Emf =   A B ω = π R 2 B ω = 3 . 14 × 0 . 1 × 0 . 1 × 3 × 10 - 5 × π 0 . 2 = 15

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