If your equation is in vertex form, then the axis of is: x= h in the general vertex form equation y = (x-h)2 + k. If your equation is in standard form, then the formula for the axis of symmetry is: $$ x = \frac {-b}{ 2a} $$ from the general standard form equation $$ y = ax^2 +bx + c $$.
Lesson Summary. All magnetic fields are created by moving charged particles. Stationary charged particles do not generate magnetic fields. An electromagnet is a magnet that relies on an electric current to produce the magnetic field. The simplest electromagnet is simply a wire carrying a current, which generates a magnetic field all around the wire.
In a power plant generator, however, the conducting coils are stationary and it is the magnets that are turned. Also, the magnetic field in power plant generators is produced by electromagnets (instead of permanent magnets) with current supplied by an external power source.