Calculating average power using impedance and rms current

AI Thread Summary
The discussion revolves around calculating the average power absorbed by a load with an impedance of 56 + j15 ohms and a current of 21 A rms. The correct formula used is P = Irms^2 * R, with the impedance converted to polar form yielding approximately 57.9741 ohms. The calculated average power is 25.5 kW. A question arises regarding the power dissipated specifically in the j15 ohm inductor and whether it should be included in the overall power dissipation calculation. The conversation emphasizes the importance of understanding the role of reactive components in power calculations.
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Homework Statement



Calculate the average power (P) absorbed by the load shown below when its impedance is 56 +j15 ohms 21 A rms?
Answer to three significant figures

Homework Equations



P=Irms^2*R

The Attempt at a Solution



Converting 56 +j15 to polar form yields 57.9741 ohms @ 14.9951 degrees
So 21^2*57.9741 = 25.5kW
 
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pokie_panda said:

Homework Statement



Calculate the average power (P) absorbed by the load shown below when its impedance is 56 +j15 ohms 21 A rms?
Answer to three significant figures

Homework Equations



P=Irms^2*R


The Attempt at a Solution



Converting 56 +j15 to polar form yields 57.9741 ohms @ 14.9951 degrees
So 21^2*57.9741 = 25.5kW

"Load shown below"??

Anyway,
What is the power dissipated in the j15 ohm inductor?

Should you be including it in your power dissipation calculation? You had the right formula!
 
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