COMEDK · Physics · 22. Electromagnetic Induction
In an inductor of self-inductance \(2 \mathrm{~mH}\), current changes with time (in sec) according to the relation, \(I=(3 t^2-3 t+8) A\). The emf becomes zero at
- A 0.5 sec
- B 6 sec
- C 2 sec
- D 5 sec
Answer & Solution
Correct Answer
(A) 0.5 sec
Step-by-step Solution
Detailed explanation
The induced electromotive force (emf) in an inductor is given by the formula \(\varepsilon = -L \dfrac{dI}{dt}\). Given \(L = 2 \text{ mH} = 2 \times 10^{-3} \text{ H}\) and \(I = 3t^2 - 3t + 8\). Differentiating the current \(I\) with respect to time \(t\):…
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