(adsbygoogle = window.adsbygoogle || []).push({}); 1. The electric power P is dissipated by a light bulb of resistance R is P=v^2/R, where V represents the line voltage. During a brownout, the line voltage is 10.0% less than its normal value. How much power is drawn by a light bulb during the brownout if it normally draws 100.0 W (watts)? Assume that the resistance does not change.

2. P = V^2/R

3. Since resistance does not change, I disregarded it completely. I then took 100 in place for P and solved for V in the equation. Then I took 10 (my solution to the first problem) in place of V and subtracted 10.0% to find the power that is drawn by the lightbulb during the brownout. But my answer does not match up to the books.

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# Homework Help: Power Dissipated by a Lightbulb

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