Here's why:
* How they work: Car batteries are lead-acid batteries. They use chemical reactions to convert stored chemical energy into electrical energy. This process produces a direct flow of electrons in one direction, resulting in DC current.
* What they power: Most components in a car, like the starter motor, headlights, and radio, run on DC power.
Note: While car batteries themselves produce DC, the alternator (which charges the battery) generates AC (Alternating Current). This AC is then converted to DC by a rectifier before it enters the battery.
