Quick question on 3 phase before my final

[tanky322]

Quick question on 3 phase before my final!

Homework Statement

In equations for 3 phase power there is an angle that is mentioned, but I don't know if this is the angle of the impedance or another angle. I am a little confused. The equations are below.

Homework Equations

P=(VrmsIrms)cos($$\theta$$)
Q=(VrmsIrms)sin($$\theta$$)


Any help?

 

[PhanthomJay]

Homework Statement

In equations for 3 phase power there is an angle that is mentioned, but I don't know if this is the angle of the impedance or another angle. I am a little confused. The equations are below.

Homework Equations

P=(VrmsIrms)cos($$\theta$$)
Q=(VrmsIrms)sin($$\theta$$)


Any help?

I'm certainly not an electrical expert, but the angle you are referring to is the phase angle between the voltage and the current, where $$cos\theta = power factor$$. For purely resistive loads, theta is 0, hence the power factor is unity, and there is no reactive power Q. However, I don't quite understand your equation, since typically ,for power transmsission, $$P= \sqrt3(V)(I)cos\theta$$. That's about it for my electrical knowledge.