CHAPTER 8 ELECTROMAGNETIC WAVES
- An accelerating charge produces electromagnetic waves.
- Electromagnetic waves carry energy as they travel through space and this energy is equally shared by the electric and magnetic fields.
- Electromagnetic waves transport momentum as well. When these waves strike a surface, a pressure is exerted on the surface.
- The spectrum of electromagnetic waves stretches over an infinite range of wavelengths. Different regions are known by different names: gamma rays, X-rays, ultraviolet rays, visible rays, infrared rays, microwaves and radio waves.
- These regions interact with matter via their electric and magnetic fields which set in oscillation charges present in all matter.
- The absorption, scattering, etc. depend on the wavelength of the electromagnetic wave and the nature of the atoms and molecules in the medium.