(adsbygoogle = window.adsbygoogle || []).push({}); Need help on these problems!!

Hello all,

I just need a little direction on these problems. Any help that you could give me would be appreciated.

1) A typical american family used 900 kWh of electricity a month. What is the average current in the 120 V power line to the house? On average, what is the resistance of a household?

2) A standard 100 W (120 V) lightbulb contains a 7.90 cm-long tungsten filament. The high-temperature resistivity of tungsten is 9.0*10^-7 m. What is the diameter of the filament?

3) An isolated 4.60 uF parallel-plate capacitor has 4.40 mC of charge. An external force changes the distance between the electrodes until the capacitance is 2.20 uF. How much work is done by the external force?

Thanks for any help you can give me on these, I have solved all the 7 others and cant seem to arrive at the correct answer for these.

Thanks,

Dennis

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# Homework Help: Need help on these problems

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