Alternating Current
In ac, the polarity reverses at regular intervals. The instantaneous amplitude (that is, the amplitude […]
Alternating-Current Basics
Period and Frequency
In a periodic ac wave, the kind that is discussed in these topics (and throughout […]
The Sine Wave
A sine wave. The period is the length of time it takes for one cycle […]
Square Waves
On an oscilloscope, a square wave looks like a pair of parallel, dashed lines, one […]
Sawtooth Waves
Some ac waves rise and/or fall in straight, sloping lines as seen on an oscilloscope […]
Complex and Irregular Waveforms
As long as a wave has a definite period, and as long as the polarity […]
Frequency Spectrum
An oscilloscope shows a graph of amplitude as a function of time. Because time is […]
Fractions of a Cycle
Engineers break the ac cycle down into small parts for analysis and reference. One complete […]
Expressions of Amplitude
Amplitude is also called magnitude, level, strength, or intensity. Depending on the quantity being measured, […]
The Generator
Alternating current can be generated by a rotating coil of wire inside a powerful magnet, […]
Why Alternating and Not Direct?
Do you wonder why ac is used at all? Isn’t it a lot more complicated […]