What is the primary function of an alternator?

The primary function of an alternator is indeed to deliver alternating current (AC). An alternator generates electricity by converting mechanical energy from the engine, typically through the use of a rotating magnetic field and conductive coils. This process results in the production of AC electrical energy, which is essential for various automotive and electrical systems.

In the context of vehicles, the alternator is crucial for recharging the battery and supplying power to the electrical components while the engine is running. The output is usually in the form of AC, which is then converted to direct current (DC) by the vehicle’s rectifier to charge the battery and power the vehicle's electrical systems.

This function is critical for ensuring the reliability and efficiency of the electrical system, which is why the delivery of alternating current is accurately identified as the correct answer.