A typical "light dimmer" used to dim the stage lights in a theater consists of a variable inductor L (whose inductance is adjustablebetween zero and Lmax) connected in series with a lightbulb B as shown in the figure. The electrical supply is 120 V (rms) at 60.0 Hz;the lightbulb is rated as 120 V, 1000 W. (a) What Lmax is required if the rate of energy dissipation in the lightbulb is to be varied by afactor of 5 from its upper limit of 1000 W? Assume that the resistance of the lightbulb is independent of its temperature. (b) Whatwould be the maximum resistance of a variable resistor (adjustable between zero and Rmax) which can be used in place of aninductor?ВlellTo energysupply(a) NumberUnits(b) NumberUnits

(a) Bulb's resistance is, R=V02PT=120 V21000 W=14.4 Ω

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