HW 12-1: (510) 41; Supp #1-4
HW 12-1: (510) 41; Supp #1-4
1. (a) Find the speed of light in water. Give your answer in m/s. (b) Find the speed of
light in water as a percentage of the speed of light in a vacuum. (Assume the light
has a wavelength of 589 nm.)
2. (a) Find the speed of light in diamond. Give your answer in m/s. (b) Find the speed of
light in diamond as a percentage of the speed of light in a vacuum. (Assume the light
has a wavelength of 589 nm.)
HW 12-1: (510) 41; Supp #1-4
Find the wavelength of light in (a) water and (b) diamond. Assume that the light started in a
vacuum with a wavelength of 589 nm before entering the water or diamond.
Humans see light of 590 nm as yellow and light of 440 nm as
purply-blue. Before light hits the retina at the back of your eye
it passes through the orb of your eye which contains a clear
fluid made mostly of water. (a) When your retina registers
yellow light, what’s the wavelength of the light as it hits your
retina? (b) Explain why you don’t see it as blue.
You don’t see it as blue because
the way light interacts with your
retina is based on the frequency,
which doesn’t change as it enters
your eye. The frequency of light
determines its energy and dictates
the way it interacts with matter.
Problem 3a says that light
that starts at 589 nm
(yellow) in air changes to a
wavelength of 442 nm in
water. That’s its wavelength
value as it hits the retina - NOT its frequency.