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2.1 The sine wave

Outcome 1 of 6 in domain 2 · Alternating current and signals

Amplitude, frequency, phase, RMS value.

My targets

I declare:

Read peak and peak-to-peak amplitude and period off an oscillogram, and derive frequency and RMS value.
Explain why "120 V" mains peaks at 170 V and what that changes for a filter capacitor.
Measure the same sine wave with the multimeter (RMS) and the oscilloscope (peak) and reconcile the two numbers.
Say what a phase shift means between two signals and measure it.
Distinguish average, RMS and peak values, and represent a sine wave as a phasor to add two out-of-phase signals.
Diagnosis: a multimeter giving a "wrong" value on a square wave, explain (true RMS or not) and prove it on the scope.

Read

Kuphaldt, Lessons in Electric Circuits, volume II (AC), chapter 1:

Basic AC theory. "What is alternating current (AC)?" for the transformer that only works with it; "AC waveforms" for the sine table from 0 to 360 degrees, the period, the frequency and the hertz; "Measurements of AC magnitude", the section that counts, for the peak, the average, RMS defined by the heat in an equal resistance, the form factor 1.11 and the needle "mis-calibrated" on purpose; "AC phase" for leading and lagging. Neither Edison nor Steinmetz in his pages; they are told here.