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A coil has resistance 10 Ω, and the magnetic flux linked with it changes with time according to ϕ = 4t² + 2t + 1 (in weber). The current induced in the coil at t = 1 s is
- 0.5 A
- 2 A
- 1.5 A
- 1 A
Correct answer: 1 A
Solution
The induced electromotive force (emf) in the coil can be calculated using Faraday's law of electromagnetic induction, which states that the induced emf is equal to the negative rate of change of magnetic flux. By differentiating the given flux function and applying Ohm's law (V = IR), we find that the current at t = 1 s is 1 A.
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