Question 91Electricity/Electronics - QMED70% to pass
What will happen to an electrical coil when the direct current flowing through the coil is increasing?
AI Explanation
The correct answer is B) the increasing current produces a voltage in opposition to the applied voltage.
When the direct current flowing through an electrical coil is increasing, the changing magnetic field inside the coil induces a voltage that opposes the change in current, as described by Lenz's law. This induced voltage is called a "back EMF" (electromotive force) and acts to counter the applied voltage, slowing the rate of increase in current. The other options are incorrect because:
A) The power consumed by the coil actually increases with the increasing current.
C) The impedance of the coil does not change, only the voltage across it.
D) The amount of magnetic flux produced actually increases with the increasing current.
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