A typical light dimmer used to dim the stage lights in a theater consists of a variable inductor L (whose inductance is adjustable between zero and L max) connected in series with a lightbulb B, as shown in Figure. The electrical supply is 120 V (rms) at 60.0 Hz; the light bulb is rated at l20 V 1000 W.(a) What L max is required if the rate of energy dissipation in the lightbulb is to be varied by a factor of 5 from its upper limit of 1000 W? Assume that the resistance of the lightbulb is independent of its temperature.(b) Could one use a variable resistor (adjustable between zero and R max) instead of an inductor? (c) If so, what R max is required?(d) Why isn't thisdone?

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L. lell To energy supply