Transformer question, please help!!

Question

48 kW of power is available from a generator, at 240V, from transmission to consumers in a town some distance from the generator. The transmission lines over which the power is transmitted have a resistance of 1ohm.

a) how much power is lost if the power is transmitted at 240 volts?

b) what would be the votlage at the end of the transmission lines?

Answer 1

v=ir

p=iv

r=1 ohm v=240v

p= V squared /r

p= 240 * 240 / 1

p= 57.6 Kw

total power loss

nearly 0 volts available

this is why high voltage is used to transmit ac

Answer 2

The 1 Ohm line resistance will simply be added to the load - which is not given in the question.

The generator's ability to produce 48kW at 208 volts is not the load - only the potential.

The equations generally used to compute these types of problems when enough data is given are relatively simple:

E=voltage   I=current(amps)   R=resistance(Ohms)  P= power(watts)

P=IE

E=IR

Answer 3

At full load, 48 kW and 240V gets your a current of 48000/240 = 200 amps.

At 1 ohm resistance, there is a drop of 200 volts on the line, so you have only 40 volts at the end of the line, assuming the load is such that the generator is running at full capacity.

power loss is 200v x 200a = 40000 watts.

.