A rotating magnetic field is a magnetic field

Magnetic field

A magnetic field is a mathematical description of the magnetic influence of electric currents and magnetic materials. The magnetic field at any given point is specified by both a direction and a magnitude ; as such it is a vector field.Technically, a magnetic field is a pseudo vector;...

 which changes direction at (ideally) a constant angular rate. This is a key principle in the operation of the alternating-current motor

AC motor

An AC motor is an electric motor driven by an alternating current.It commonly consists of two basic parts, an outside stationary stator having coils supplied with alternating current to produce a rotating magnetic field, and an inside rotor attached to the output shaft that is given a torque by the...

. Nikola Tesla

Nikola Tesla

Nikola Tesla was a Serbian-American inventor, mechanical engineer, and electrical engineer...

 claimed in his autobiography that he identified the concept of the rotating magnetic field in 1882

1882 in science

The year 1882 in science and technology involved some significant events, listed below.-Biology:* Robert Koch isolates the Tuberculosis bacillus.* Élie Metchnikoff discovers phagocytosis.-Chemistry:...

. In 1885, Galileo Ferraris

Galileo Ferraris

Galileo Ferraris was an Italian physicist and electrical engineer, noted mostly for the studies and independent discovery of the rotating magnetic field, a basic working principle of the induction motor...

 independently researched the concept. In 1888, Tesla gained for his work. Also in 1888, Ferraris published his research in a paper to the Royal Academy of Sciences in Turin

Turin

Turin is a city and major business and cultural centre in northern Italy, capital of the Piedmont region, located mainly on the left bank of the Po River and surrounded by the Alpine arch. The population of the city proper is 909,193 while the population of the urban area is estimated by Eurostat...

.

The rotating magnetic field is mainly utilized in electric rotating machinery

Electric rotating machinery

Electric rotating machinery includes:* Electric motor* Electrical generator* Motor-generator* Rotary transformer...

 e.g.