Final answer:
An electric generator uses mechanical energy to maintain a current in an external circuit through magnetic induction, converting mechanical energy into electrical energy. Electric motors, conversely, convert electrical into mechanical energy. option a is the correct answer.
Step-by-step explanation:
An electric generator uses the mechanical work done on it by an external system to maintain a current in an external circuit. This transfer of energy is achieved by magnetic induction. As mechanical energy is introduced to the generator, it causes wire loops within a magnetic field to rotate. This rotation in the magnetic field generates an alternating current (AC) voltage that can then be used to drive a current through an external circuit.
Generators are critical components in the production of electrical power, converting mechanical energy into electrical energy through the principle of magnetic induction.
In contrast, electric motors operate on a similar principle but in the reverse direction. They convert electrical energy into mechanical work by sending a current through loops of wire in a magnetic field, which in turn exerts torque on the loops and rotates a shaft. The primary application of electric motors is the conversion of electrical energy to mechanical energy, which is fundamental to the functioning of many mechanical systems and devices.