What type of generator produces an alternating current?

An alternator is specifically designed to produce alternating current (AC) electricity. This is achieved through its operation, which involves rotating a magnetic field within coils of wire. When the magnetic field changes, it induces an electric current in the wire, generating AC. Alternators are commonly used in various applications, including automotive systems, power plants, and renewable energy sources, due to their efficiency in producing AC power.

In contrast, an inverter converts direct current (DC) to alternating current, rather than producing AC directly. A synchronous generator also generates AC but is a specific type of generator that operates at a constant speed and frequency; although it produces AC, it is a more specialized category. An induction motor, meanwhile, is designed to convert electrical energy into mechanical energy and is not focused on generating electrical power, but rather using it to create motion.

Thus, an alternator stands out as the primary device that consistently and readily produces alternating current, making it the correct answer.