A question on alternating current

AI Thread Summary
The discussion revolves around calculating the root-mean-square (rms) voltage across a 1500W device with a peak current of 5.4A. The user correctly applies the formula for peak current to find the rms current, resulting in 3.82A. They then use the relationship between rms current, power, and rms voltage to calculate the rms voltage as 392.84V. Despite initial doubts about the simplicity of the solution, it is confirmed to be correct. The calculation process is validated, emphasizing that straightforward methods can yield accurate results.
Kudo Shinichi
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Homework Statement


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?

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.
 
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This is, in fact, the correct way to do it, easy though it may seem.
 
jdougherty said:
This is, in fact, the correct way to do it, easy though it may seem.

thank you very much^^
 

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