gen-explain-ac-versus-dc-as-you-would-to-a-capable-student-in-3-11c4

Explain AC versus DC as you would to a capable student, in 3-4 sentences.

# AC versus DC **Direct Current (DC)** flows in one constant direction, like water flowing steadily downhill—the voltage remains at a fixed polarity, with electrons always moving from negative to positive terminal (think batteries or solar panels). **Alternating Current (AC)** periodically reverses direction, typically 50-60 times per second, like water sloshing back and forth—the voltage switches polarity in a sinusoidal wave pattern (this is what comes from wall outlets). AC "won" for power transmission because it's easy to step voltage up or down using transformers, allowing high-voltage transmission that minimizes power loss over long distances, while DC is preferred for batteries and electronics because many devices need steady, unidirectional current to function properly.