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View Full Version : A question on alternating current


Kudo Shinichi
Mar16-09, 06:35 PM
1. The problem statement, all variables and given/known data
The peak value of an alternating current in a 1500W device is 5.4A. What is the rms voltage (root-mean-square voltage)across it?

3. The attempt at a solution
Peak current=sqrt(2)*Irms
5.4A=sqrt(2)*Irms
Irms=3.82A
Irms=P/Vrms
3.82=1500/Vrms
Vrms=392.84V

I am not sure whether this is the correct way to do the question or not, because it seems to simple...Any comment/help would be great. Thank you very much.

jdougherty
Mar16-09, 07:11 PM
This is, in fact, the correct way to do it, easy though it may seem.

Kudo Shinichi
Mar16-09, 07:51 PM
This is, in fact, the correct way to do it, easy though it may seem.

thank you very much^^