Question

What term is used for the spreading out of the white light into different colors inside the prism?

Answer 1

Diffraction

Explanation:

Diffraction doesn't just happen with prism, it can also happen with diffraction gratings (http://hyperphysics.phy-astr.gsu.edu/hbase/phyopt/grating.html). As the website shows you, it can also happen with any colour of light. It occurs as the light have different wavelengths.

`nlamda=dsintheta`
`n` is the order, number of bright spots from the centre
#lamda is the wavelength #d`is the distance if the spacing, or`1/("Number of slits per meter")# #theta# is the angle the bright is to the normal, or central maxima (birghtest light in the center)

From this you get `theta=sin^(-1)((nlamda)/d)`, where an increase in wavelength gives an increase in the angle it is diffracted at.