State scientists research about electricity and magnetism after Oersted's observation.

Explanation

1. After Oersted.s observation, scientists has done below research.
2. In 1864, the laws obeyed by electricity and internet magnetism were unified and formulated by James Maxwell who then realised that light was electromagnetic waves.
3. Radio waves were discovered by Hertz and produced by J. C. Bose and G. Marconi by the end of the `19^(th)` century.
4. A remarkable scientific and technological progress has taken place in the 20th century, this is due to our increased understanding of electromagnetism and the invention of devices for production, amplification, transmission and detection of electromagnetic waves.