An electric machine is a device that can convert either mechanical energy to electric energy or electric energy to mechanical energy.1 Such a device is called a generator when it converts mechanical energy to electric energy; it is called a motor when it converts electric energy to mechanical energy. Since an electric machine can convert power in either direction, any such machine can either be used as a generator or a motor. Thus, all motors and generators can be used to convert energy from one form to another using the action of a magnetic field.
A transformer is a device that converts alternating current (AC) electric energy at one voltage level to ac electric energy at another voltage level. Transformers operate on the same principles as generators and motors.
| ? | = | angular position of an object. It is the angle at which it is oriented. It is measured from one arbitrary reference point (units: radians or degrees). |
| ? | = | angular velocity = d ?/dt. It is the rate of variation of angular position with time (units: radian or degrees). |
| f m | = | angular velocity expressed in revolutions per second = ? m/2 ?. |
| ? | = | angular acceleration = d ?/dt. It is the rate of variation of angular velocity with time (units in rad/s 2). |
| ? | = | torque = (force applied) (perpendicular distance) ? (units in N m). |
| ? | = | J ? = Newton s... |
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