(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Basically, I need to understand how to calculate Irms and I*rms given a Vrms and an impedance Z.

Example question:

Given Vrms = 120 V at an angle of 30° and an impedance of Z = 10 Ω, find Irms and I*rms.

2. Relevant equations

How exactly do I solve for Irms and I*rms?

3. The attempt at a solution

I figure that Irms = Vrms / Z. However I am a bit confused as to the I*rms.

From my notes, I would imply that I just flip the sign of the angle, but this does not seem right.

My attempt:

Irms = Vrms/Z = 120angle30/10angle0 = 12angle30

And for I*rms, just flip the sign of the angle: 12angle-30

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# Homework Help: Irms, Vrms and power calculations

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