An electric field is created by a change in voltage (charge). The higher the voltage the stronger the field.
A magnetic field is created when electric current flows. The greater the current the stronger the magnetic field.
- A change in an electric field induces a change in the magnetic field.
- A change in a magnetic field induces a change in the electric field.
- An electromagnetic wave is the result of the interaction of electric and magnetic fields.
- An electromagnetic wave can be propagated when either the charge of an electric field changes or when the current of a magnetic field changes.
- Once an electromagnetic wave propagates outward it cannot be deflected by an external electric or magnetic field.