# Homework Help: Differences between dispersion and scattering?

1. Feb 23, 2016

What makes dispersion be different from scattering?
What exactly is the definition of scattering?
Google says it is to deflect or diffuse.how can deflection be a synonym for scattering? How are they related?

2. Feb 23, 2016

### Simon Bridge

It is easy to get confused because the words have more than one use depending on the context.

In common language, "dispersion" refers to a spreading out, while scattering a special way that something may get spread out.
i.e. you may disperse seeds over a field by scattering them from your hand.

Light may be scattered from an object so it is dispersed over a screen.

Be careful though: "scattering" and "dispersion" are also technical terms in physics.
"scattering" is a particular process where incoming radiation, like light, is sent off again in random directions.
"dispersion" refers to the way a pulse (of light, say) spreads out in the direction of travel.

The technical use of "scatter" is very similar to the common one, but the technical use for "dispersion" is quite different... so we have to talk about scattered light being distributed over a screen rather than dispersed.

3. Feb 23, 2016

### drvrm

scattering is a phenomena in which an incident beam of particles/light is redirected/scattered in many different directions when it interacts with a potential or particles of matter .....when sunlight strikes atoms in our atmosphere, the light is scattered in many directions...in fact, the blue light is scattered over larger angles than the red light causing the appearance of the sky blue .

dispersion is the process in which different wavelengths of light travel at different speeds when moving through a material. all wavelengths of light travel at the same speed c the velocity of light when traveling in a vacuum, but in different media the light's speed changes , and the
change is dependent upon wavelength
when light passes through a prism, different wavelengths travel at different speeds, and therefore refract (bend) at different angles...and we get a spectrum of different colors.
In common language we may confuse between the two terms but in physics we use these terma for specific experimental/theoretical frame work. for example a beam of neutrons may look like dispersed by falling on a gas media ( containing say hydrogen) but its analysis can be done only through a microscopic scattering process.