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The magnetic flux through a coil perpendicular to its plane is varying according to the relation ϕ = (5t³ + 4t² + 2t − 5) Weber. If the resistance of the coil is 5 ohm, then the induced current through the coil at t = 2 s will be,
- 15.6 A
- 16.6 A
- 17.6 A
- 18.6 A
Correct answer: 15.6 A
Solution
To find the induced current, we first calculate the induced electromotive force (emf) using Faraday's law, which states that the induced emf is equal to the negative rate of change of magnetic flux. By differentiating the given flux function with respect to time and applying Ohm's law (I = emf/R), we find that the induced current at t = 2 s is 15.6 A.
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