The time constant for the RL circuit is of the order of a few seconds. Describe what happens to the light bulb when the switch S is closed.

Question

Quizplus · Accepted Answer

When the switch S is closed, the current starts to flow through the circuit and builds up gradually to its maximum value determined by the resistance of the circuit and the applied voltage. As the current increases, the magnetic field around the inductor grows and causes the bulb to light up gradually. Once the current reaches its steady-state value, the bulb stays on as long as the switch remains closed. When the switch is opened again, the current decreases gradually to zero and the bulb goes off. The time constant of the circuit determines the rate of change of the current and the behavior of the circuit over time. In this case, since the time constant is of the order of a few seconds, the bulb will come on gradually and stay on.

The Time Constant for the RL Circuit Is of the Order