(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

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 Lmax) connected in series with a lightbulb. The electrical supply is 120 V (rms) at 60.0 Hz; the lightbulb is rated as 120 V, 1300 W. (a) What Lmax is required if the rate of energy dissipation in the lightbulb is to be varied by a factor of 4 from its upper limit of 1300 W? Assume that the resistance of the lightbulb is independent of its temperature. (b) What would be the maximum resistance of a variable resistor (adjustable between zero and Rmax) which can be used in place of an inductor?

2. Relevant equations

I know the equations for RLC circuits, and I know P = (i^2)(R)

3. The attempt at a solution

I'm really just stuck. I don't really understand the question. Are we increasing it by a factor of 4 or decreasing it? Can someone get me started on the right track?

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# Homework Help: LR Circuit

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