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Violet light bends more than red
![[April Holladay] How light bends through glass](images/light-bends3.jpg)
If the incident light is perpendicular to the glass (going
from Point A to Point B), then the light does not bend. The path AB is the
shortest path and takes the least time. But what if the light goes from
Point A to Point C? The light could zip through fast air along a line AC,
then slog through a lot of slow glass, and zip through more air to C.
That's the shortest route but it involves much slow-glass travel.
Instead, if the light went from A to "a" along a longer route,
admittedly, but going fast, then traveled a short, slow glass route from "a" to
c, and then zipped from c to C---the light would travel from A to C in less
time. That's what happens because light minimizes travel time.
The violet light must bend more than the red to lessen the
glass distance since its glass travel is even slower than the red light.
That's why violet light bends more than red. |
