A laser beam is incident at an angle of 30.0° from the vertical onto a solution of corn syrup in water. The beam is refracted to 22.84° from the vertical.
(a) What is the index of refraction of the corn syrup solution?
I already got the answer of 1.29.
(b) Assume that the light is red, with vacuum wavelength 632.8 nm. Find its wavelength in the solution.
I already got the answer of 490.5 nm.
(c) Find its frequency in the solution?
n1sin(theta)1 = n2sin(theta)2
frequency = c/wavelength
The Attempt at a Solution
I already know the answer, but I'm just confused as to why.
It's asking for the frequency in the solution, so I used f=3*10^8/490*10^-9, which got me 6.1*10^14.
However, this is wrong, and the correct answer did it like this and used f=3*10^8/632.8*10^-9, which gets you the answer of 4.74*10^14. I'm confused because if you're trying to find the frequency in the solution, why are you using the wavelength in the vacuum? Why not use the wavelength in the solution?