loss in transmission lines

[Bryden, Francis]

Hi John
Hi JohnWith transmission lines, there are two voltages to consider.


 1.  The voltage between the wires (or the terminal voltage of the transformer)
 2.  The voltage drop along the length of the wire.

You could use either equation to find the power loss as long as you realize that the "V" is the voltage drop along the length of the wire.
This is tricky to measure, so its easier to use P = I^2  R to calculate the power loss  and  P = VxI  to find the power transferred where "V" is the voltage between the wires

Fro this it is easy to see why you want a small I and a big V

regards ................ Francis


Thanks ................ Francis

Francis Bryden
HoD Physics
St Cuthbert's College
122 Market Rd               or Box 26 020
Epsom                              Epsom
Auckland 1051                   Auckland 1344
New Zealand                      New Zealand

ph: 64 9 5204159 ext 7808

fbryden at stcuthberts.school.nz<mailto:fbryden at stcuthberts.school.nz>
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