From where does an electromagnetic wave produces?

From where does an electromagnetic wave produces ? Write about characteristics of electromagnetic wave.

Electromagnetic wave is produced when an electric charge vibrates (moves back and forth).
Characteristics of electromagnetic waves :

  1. Electric field and magnetic fields are perpendicular to each other and at right angles to direction of propagation of wave.

  2. It travels with speed of light i.e., 3 x ${{10}^{8}}$ m${{s}^{-1}}$.

  3. Electromagnetic energy is characterized by wavelength and frequency .