How does a motor run?
An electric motor is a device that can produce a force when electricity is applied. The force is usually the attraction or repulsion between magnets. Usually the magnets are arranged so that the force is tangential to a fixed axis called a shaft. This produces the usual rotary motion, but it can be arranged to work in a straight line hence “linear motors”. This force then produces torque, ( a distance times a radius) , measured in ft-lbs, oz-ins, gm-cms., or some other unit like newton-meters.( If your arm were 2 feet long and you held a 6 ounce apple in your hand; the torque your arm muscles would have produce, to cancel the weight of the apple, would be about one newton-meter).
