Tic
Complex motor tics are typically more purposeful-appearing and of a longer nature. They may involve a cluster of movements and appear coordinated. Examples of complex motor tics are pulling at clothes, touching people, touching objects, echopraxia (repeating or imitating another person's actions) and copropraxia (involuntarily performing obscene or forbidden gestures).
Timeline of United States inventions (before 1890)
An induction motor is an AC electric motor in which the electric current in the rotor needed to produce torque is induced by electromagnetic induction from the magnetic field of the stator winding instead of using mechanical commutation (brushes) that caused sparking in earlier electric motors. They are also self-starting. The Serbian-American inventor Nikola Tesla explored the idea of using a rotating magnetic induction field principle, using it in his invention of a poly-phase induction motor using alternating current which he received a patent for on May 1, 1888. The rights to Tesla's invention were licensed by George Westinghouse for the AC power system his company was developing.