- There are two types of electrical current flow; direct current (DC) and alternating current (AC).
- DC flows in one direction only and is the primary type of current used in logic and control circuits.
- AC alternates in polarity, flowing back and forth, and is the main type of current found in household electrical mains.
- AC is the typical current used to power appliances, and is often converted to DC within an appliance to power the logic circuit boards.
- Mapping the polarity of household AC over time reveals a sine wave, but it may also have other waveforms.
- AC is described by its period (cycle time), frequency (cycles per second, measured in hertz (
hz)), and amplitude (magnitude of waveform measured in volts).
Part 4: Resistance and Ohm’s Law