- #1
Larfleeze
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Homework Statement
A factory receives 120kW of power from a power station 20km away via transmission lines. If the resistance in the power lines is 0.5Ω/km, what is the power loss in the lines if the electricity is transmitted at 100kV (Approximate to a simple DC circuit).
Homework Equations
V = IR
P = VI = I2R = V2/R
The Attempt at a Solution
Now first I simply found the total resistance in the wires by
Rw = 20km * 0.5Ω/km = 10Ω
The DC circuit I then approximated consisted of 2 resistors, one representing the total resistance from the wires and the other being the load of the factory. Since the question states the voltage is transmitted at 100kV I used that as the EMF and set up my imaginary circuit thusly:
http://img15.imagevenue.com/img.php?image=951360451_Circuit_122_536lo.jpg
However, it appears at this point I don't have enough information to answer the question, since I don't have the current or the Voltage over either resistor. Am I missing something or is there an easy solution I'm just not seeing?
(I'm not very knowledgeable in this area of Physics, only did it in my first year of my undergrad, but I am mathematically inclined so I don't think I'll be frightened by the solutions... hopefully)