Question

Why does light particles stay together and don't disperse? Do phtons travel with same pace, if yes why?

Answer 1

Dispersion of light do not occur in vacuum or air because the boundaries of the prism are not parallel. The only reason is that the walls of the glass slab are parallel, so the dispersion is reversed. Basically,light does get dispersed in air or vacuum, whenlight enters from any other medium.

All photons move at the speed of light. Different colors, or EM radiation throughout the spectrum have different FREQUENCIES, they all travel at the same speed "C".


The speed of light, (or the speed of a photon) in a near-perfect vacuum is exactly 186,282 miles per second. We perceive photons (light) traveling at this speedbecause they are massless, or have no 'weight' (but they do have kinetic energy, more on that in a bit).