A generating station is producing 1.4e6 W of power that is to be sent to a small town located 7.0 km away. Each of the two wires that comprise the transmission line has a resistance per kilometer of length of 5.0e-2 [tex]\Omega[/tex]/km.(adsbygoogle = window.adsbygoogle || []).push({});

(a) Find the power lost in heating the wires if the power is transmitted at 1100 V.

(b) A 70:1 step-up transformer is used to raise the voltage before the power is transmitted. How much power is now lost in heating the wires?

Heres what I did:

a) P = 1.4e6 W

L = 7.0 km

R/L = 5.0e-2 ohm/km

Vp = 1100 V

R = (5.0e-2 ohm/km)*(7.0km)

R = .35 ohm

I = P/V = 1.4e6W/1100V = 1272.73A

P = I^2 * R = (1272.73)^2 * (.35ohm)

P = 5.7e5 W

But it is wrong....

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# Homework Help: How much power is lost in heating the wires of a power line

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