An extension cord made of two wires of diameter 0.129 cm (no. 16 copper wire) and of length 2.7 m is connected to an electric heater which draws 15.0 A on a 120V line. How much power is dissipated in the cord?(adsbygoogle = window.adsbygoogle || []).push({});

Do I just use P=IV?

But that leaves a lot of "extraneous" information.

My second thought was to find resistance:

R = p (L/A)

A = pir^2 = 1.29E-3^2 x pi = 5.23E-6

R = (1.68E-8) x (2.7/5.23E-6)

R = .00867

But then I'm not sure what to do from there.

Using P=IV I get 1800 W. But then do I have to multiply by length and area?

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# Homework Help: Extension cord connected to heater - Find the power

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