An electric motor converts electrical energy into mechanical work, usually rotation, through electromagnetic forces. For a coil with turns, area and electric current in a uniform magnetic field , the torque magnitude iswhere is the angle between the coil's normal and the magnetic field. Repeated rotation requires the current or effective field arrangement to keep supplying torque in the intended direction. Electrical input power must cover useful output plus losses.
A coil with , , and has maximum torque . At angular speed , instantaneous mechanical power is ; the maximum-torque value alone does not specify a motor's sustained output.
Michael Faraday's 1821 rotation experiment made the conversion visible: a current-carrying wire moved around a fixed magnet while a pool of Mercury maintained electrical contact. The Royal Institution preserves his 1822 apparatus, consisting of a wire, glass vessel and fixed bar magnet connected through the conducting liquid. Continuous rotation, rather than a single deflection, established a route from steady electric current to repeated mechanical motion.[ref]
Michael Faraday's electric magnetic rotation apparatus by Royal Institution. Collection description, 1821 discovery and surviving 1822 apparatus
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An electric motor is a device that converts electrical energy into mechanical energy through the interaction of magnetic fields and current-carrying conductors. Electric motors operate based on electromagnetic principles and are commonly used in various applications, ranging from household appliances to industrial machinery. ### Key Components of an Electric Motor: 1. **Stator**: The stationary part of the motor that produces a magnetic field. It typically consists of coils of wire wound around a core.
