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 short, currents help to create magnetic fields. A moving or changing magnetic field does produce a current in a current loop or a voltage across the ends of a current loop. This is called electromagnetic induction and the current or voltage is called an induced current or an induced voltage. Electrical Induction.n short, currents help to create magnetic fields. A moving or changing magnetic field does produce a current in a current loop or a voltage across the ends of a current loop. This is called electromagnetic induction and the current or voltage is called an induced current or an induced voltage. Electrical Induction.