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Reefy
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Homework Statement
Not sure if this is the correct place for Electrical Engineering Homework help but here goes
A single-phased motor connected across a 240-V source at 50Hz as shown in the figure has a power factor of 1.0, I = 20A, I1 = 25 A.
Find the capacitance required to give a unity power factor when connected in parallel with the load as shown.
Homework Equations
Apparent Power S = VRMSIRMS
Angular Frequency ω = 2πf
cosθ = 1.0
Reactive Power Q = Ssinθ = VRMSIRMSsinθ
Active Power P = Scosθ = VRMSIRMScosθ
ZRL = R + ωLi
Zequiv = ZCZR/[ZC + ZR]
QC = 1/ωC
The Attempt at a Solution
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I think I am misunderstanding the question because if it is already at unity, wouldn't that make θ = 0° meaning QL = 0 VAR?
If we want this at unity, QL = QC, correct? But I am getting 0 when the answer is allegedly non-zero.
The only thing I was able to find was P = (240 V)(20 A) = 4800 W and I think I2 = 5 A which is entering the node. Meaning I1 = I + I2. This I2 is an RMS value, correct?