H

#### henry chow

- Jan 1, 1970

- 0

I thank everyone for answering my question. Right now I get a better

understanding now because the V (voltage) (used on the power calculation) is

measured across the single line rather than between the two high-voltage

lines which is over ten thousand volts.

Here is another "basic" question on a transformer. Suppose I have a

transformer with a primary windings of 100 turns and a secondary windings of

200 turns. If I apply an AC voltage of 100 volts and 2 A to the primary, I

will get an AC voltage of 200 volts and 1A from the secondary.

If I put a load of, say 50 ohms, across the secondary windings output, what

should the current be? According to Ohms' law, it should be I=V/R=200

volts/50 ohms=4 A. But the max current you can get from the secondary

windings is 1A. Why the contradiction? If the current across the load is

1A, should the voltage drop across the load be V=IR=1A * 50 ohms=50 volts,

which is not right because the secondary windings have a voltage of 200

volts? Can you explain the contradiction?

Again, suppose instead I apply a load of 400 ohms to the secondary windings,

I should get a current of 200 volts/400 ohms=0.5 A? Is that correct? Then

what happens to the 1A I am supposed to get from the secondary windings?