Learning module

AC vs DC

DC flows one way. AC changes direction repeatedly and is used for power distribution.

Safety first, always.

ElectroLab AI teaches theory, low-voltage electronics, and planning concepts. Mains voltage, switchboards, fixed wiring, high-current systems, and legal electrical work must only be performed by licensed electricians where required.

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Academy progress

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Mark lessons as complete as you work through the bench checks, then use the quiz to test the ideas.

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Current lesson

AC vs DC

Start here

Build a low-voltage LED circuit from a battery, then compare it with a safe signal-generator waveform on the simulator canvas.

Key ideas

Direct current has a fixed polarity, so positive and negative connections matter for LEDs, batteries, modules, and electrolytic capacitors.

Alternating current repeatedly changes polarity. In most power systems it is described by frequency and RMS voltage rather than just peak voltage.

AC can be stepped up or down with transformers because a changing current creates changing magnetic flux.

Many electronics projects convert AC to DC using rectifiers, smoothing capacitors, and regulators.

Useful formulas

Vpeak = Vrms x 1.414

Period = 1 / frequency

Power in DC load = V x I

Bench checks

Use a multimeter in DC mode on batteries and DC modules.

Use AC mode only when measuring a known low-voltage AC source or transformer secondary.

On a scope, compare a battery trace with a low-voltage AC waveform from a safe signal source.

Common mistakes

Measuring AC with the meter set to DC and thinking the source is dead.

Ignoring polarity on DC parts that can be damaged backwards.

Treating mains AC as a bench experiment instead of licensed electrical work.

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