For cyclical processes, such as rotation, oscillations, or waves, frequency is defined as a number of cycles per unit time. In physics and engineering disciplines, such as optics, acoustics, and radio, frequency is usually denoted by a Latin letter f or by the Greek letter or Î½ (nu) (see e.g. Planck's formula).
An inductor, also called a coil or reactor, is a passive two-terminal electrical component that stores electrical energy in a magnetic field when electric current is flowing through it. An inductor typically consists of an electric conductor, such as a wire, that is wound into a coil. When the current flowing through an inductor changes, the time-varying magnetic field induces a voltage in the conductor, described by Faraday's law of induction. According to Lenz's law, the direction of induced electromotive force (e.m.f.) opposes the change in current that created it.
Mutators. A mutator is a method that can modify an object. In the simplest case, a mutator just assigns a new value to one of the fields. In general, a mutator performs some computation and modifies any number of fields.Sometimes, accessors are called 'getter' methods and mutators are called 'setter' methods.n accessor is a method that accesses the contents of an object but does not modify that object. In the simplest case, an accessor just returns the value of one of the fields. In general, an accessor performs some computation using the fields as long as that computation does not modify any of the fields.