Definition - What does Motor mean?
A Motor is an electric machine that is used to convert one form of energy to mechanical energy. An electric generator performs the reverse procedure, i.e., it converts mechanical energy to electrical energy. In the normal mode of motoring, most of the electric motors are operated by the interaction between the winding currents and magnetic fields of the Motors. The Motors can be classified by internal construction, type of motion output, application and type of electric power source.
Petropedia explains Motor
Motors can be divided into two groups, i.e., the alternating current motors (AC motors) and direct current motors (DC motors). The designs of motors are different but their fundamental is the same. When an electric current flows with a wire loop which is in a magnetic field, the loop starts rotating and this rotating motion gets transmitted to the shaft which provides useful mechanical work. The Motors basically use magnets to generate the motion.
When the useful energy is transferred, some energy that is not useful, known as wasted energy, is also transferred. To measure the efficiency of any device, the useful energy is required to be measured.