Which part serves as a high-voltage transformer in a vehicle?

The ignition coil functions as a high-voltage transformer in a vehicle. It converts the low voltage from the car's battery (typically 12 volts) into a much higher voltage, which is necessary to create a spark in the spark plugs. This high voltage is essential for igniting the air-fuel mixture in the engine's combustion chamber, thereby facilitating the engine's operation.

Understanding the role of the ignition coil highlights its importance in the ignition system. When the ignition key is turned on, the coil generates a high-voltage pulse that travels through the ignition system to the spark plugs. This process is critical for starting the vehicle and maintaining its running efficiency.

The other components listed, such as the starter motor and alternator, serve different functions. The starter motor is responsible for cranking the engine, while the alternator generates electrical power to recharge the battery and power the vehicle's electrical systems. The distributor cap is part of the ignition system that routes the high voltage to the correct spark plug at the right time, but it does not transform voltage like the ignition coil does.