A 76 W light bulb with a resistance of 179 Ω is connected to a power supply with a 117 V. What is the internal resistance of the power supply? Express the answer with one decimal place.(adsbygoogle = window.adsbygoogle || []).push({});

So my attempt has been this but I'm not exactly sure whether or not so just making sure this would be the answer.

[117/(179+r)]^2(179)=76

sqrt(76/179)=0.652 A

(0.652 x 179)= 116.708

117-116.708=0.364

0.364/0.652=0.558 ohm

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# Homework Help: What is the internal resistance of the power supply

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