Which component converts electrical energy into mechanical energy in a vehicle?

The starter motor is the component in a vehicle that converts electrical energy into mechanical energy. When the ignition key is turned, the vehicle's battery sends electrical current to the starter motor, initiating a mechanical process that cranks the engine. This action is essential for starting the vehicle, as it helps to turn the engine and prepare it for combustion.

The starter motor operates through the interaction of electrical coils and a magnetic field, which creates rotational movement (mechanical energy) necessary to engage the engine's flywheel. With the starter motor functioning correctly, the engine can begin its cycle, leading to proper vehicle operation.

In contrast, other components like the generator are primarily responsible for converting mechanical energy back into electrical energy to recharge the vehicle’s battery while the engine is running. Relays serve as electrical switches that control the flow of current to various components but do not perform energy conversion. Diodes are used for directing current and preventing backflow, but again, do not convert energy types. Thus, the unique role of the starter motor as the component that facilitates the conversion of electrical energy into mechanical energy is what makes it the correct choice.