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quanticism
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Homework Statement
In Australia, New South Wale's final year of high school, a common question is asking something like:
How does distributing electricity at high voltages reduce power loss in the transmission lines.
Homework Equations
P = VI = (I^2)R = (V^2)/R. Not very clear without subscripts.
The Attempt at a Solution
I attached an image http://imageshack.us/f/16/image0001lmg.jpg/
R_wire is the resistance of the transmission lines
R_load is the load
All the textbooks and teachers will teach it as shown in Case1 which essentially says:
P_input = V_supply * I = constant
If we distribute at high V_supply, current I must fall (since P_input is constant).
Since current I falls, P_loss = I^2 * R_wire must also fall.
But what about Case 2? Using P_loss = V_wire^2/R_wire seems to end up with a contradictory result.