Calculating Power Output of a 580W Heater in the US

jdoggigs
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Homework Statement


A 580w heater is designed for use in Germany, where electric outlets supply 230V(rms) service. What is the power output of the heater when plugged into a 120V(rms) outlet in the U.S.? Ignore the effects of temperature on the heater's resistance.


Homework Equations



barP=I(rms)V(rms)

The Attempt at a Solution


I tried to fine I(rms) by first calculating for I in germany: I(rms)=(580w)/(230V).
Then I used this I(rms) to calaulate U.S. power output; barP=(I(rms))(120V).
This did not give the correct answer.
Would I have to consider that germany uses DC and U.S. uses AC, is there a conversion for this?
Thanks
jdoggigs
 
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Irms will be different in the US than it is in Germany. However, one out of the 4 usual variables will be the same. Question for you: which one?

(The 4 usual variables are V, I, R, and P.)
 
jdoggigs said:

Homework Statement


A 580w heater is designed for use in Germany, where electric outlets supply 230V(rms) service. What is the power output of the heater when plugged into a 120V(rms) outlet in the U.S.? Ignore the effects of temperature on the heater's resistance.


Homework Equations



barP=I(rms)V(rms)

The Attempt at a Solution


I tried to fine I(rms) by first calculating for I in germany: I(rms)=(580w)/(230V).
Then I used this I(rms) to calaulate U.S. power output; barP=(I(rms))(120V).
This did not give the correct answer.
Would I have to consider that germany uses DC and U.S. uses AC, is there a conversion for this?
Thanks
jdoggigs

Btw, Germany does use AC. No country (as far as I know) uses DC as mains.
 
Irms is what I need to find th US power outout, I have no resistance, P is the answer I'm
looking for, so voltage is the same. I'm lost here how does this help?
I assumed that Europe used DC because You need different plugs there.
 
Okay after some consideration of the question asked, I figured it out.
Thanks for all the help'
 
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