What is the primary function of an electric motor in control systems?

The primary function of an electric motor in control systems is to convert electrical energy into mechanical energy. This process is fundamental to the operation of various machines and devices that rely on motors for movement and operation. When electrical energy is supplied to an electric motor, it generates motion through the interaction of magnetic fields within the motor's components, such as the stator and rotor. This conversion is critical in a wide range of applications, from industrial machinery to household appliances, enabling them to perform tasks that require mechanical power.

In contrast, the other options describe processes that do not relate to the function of electric motors. For instance, thermal energy to electrical energy conversion is typically associated with generators and thermoelectric devices, while chemical energy to mechanical energy conversion pertains to engines that use fuel combustion. Storing electrical energy for later use refers to batteries or capacitors, which serve a different purpose altogether. The clarity of the motor's role in utilizing electrical energy to produce useful mechanical work underscores its significance in control systems.