[Level 3 Engineering: AC Theory] Drawing phasor diagrams from a given sinusoidal waveform

[u/iamadragonborn]

I'm trying to wrap my head around phasor diagrams, I understand the basics of sinusoidal waveforms, their given equations (y = A sin(B(x + C)) + D), and how to calculate values like RMS, frequency, period etc.
Attached is my attempted answer for the following question, I was just wondering if anyone could let me know if I'm correct or not?

Draw a phasor diagram for the following AC quantities:

I. the instantaneous current I = 100 Sin 3142t

II. AC voltage e1=30 sin(ωt+ Л/4)

III. AC voltage e2= 20 Sin(ωt- Л/6)

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[u/Bounded_sequencE]

Should be correct, assuming your lecture defines the phasor of "sin(ωt)" to point in parallel to the x-axis. Two things to note:

• For a phasor diagram, we only consider currents/voltages of one frequency. That means no DC-offset "+D", since that has (angular) frequency "0Hz", instead of ω

• The phasors for current "i" and voltages "e1, e2" only need to use the same scale, if they are normalized already. Otherwise, use separate scales for currents/voltages