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NEET2020PhysicsElectromagnetic InductionActual

The magnetic flux linked with a coil (in Wb ) is given by the equation ϕ = 5 t 2 + 3 t + 16 . The magnitude of induced emf in the coil at the fourth second will be:

Options

  1. A33   V
  2. B43   V
  3. C108   V
  4. D10   V

Correct answer

B. 43   V

Step-by-step solution

Given magnetic flux in terms of time, ϕ = 5 t 2 + 3 t + 60 , and we know that from Faraday's law of electromagnetic induction, rate of change of flux is directly related to induced EMF of the coil, ⇒ | ε | = d ϕ d t = 10 t + 3 At t = 4   s , | ε | = 40 + 3 = 43   V

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