<p>I REALLY need help on this problem.</p>
<p>The glass prism shown above has an index of refraction that depends on the wavelength of the light that enters it. The index of refraction of 1.50 for red light of wavelength 700 nanometers (700 X 10^-9 m) in vacuum and 1.60 for blue light of wavelength 480 nanometers in vacuum. A beam of white light is incident from the left, perpendicular to the first surface, as shown in the figure, and is dispersed by the prism into its spectral components.</p>
<p>a) determine the speed of the blue light in the glass.
b) determine the wavelength of the red light in the glass.
c) determine the frequency of the red light in the glass.</p>
<p>The glass prism is a 30-60-90 right triangle. That looks like this. The white light is entering perpendicular to the 30-90 side. </p>
<h2>30</h2>
<h2>-</h2>
<p>-90----60</p>
<p>Thanks for your help in advance.</p>
<p>AP Physics B :rolleyes:</p>
<p>for "a" i got 1.875 X 10^8 but i'm not sure if it's right. The rest I have no clue. If i knew "b" i could get "c"</p>
<p>what's with the sarcastic face?</p>
<p>well, upon refraction, the frequency doesnt change. the wavelength changes (and thus the speed also). i think that should help.</p>
<p>i am pretty confidently that what i said was true.
the frequency is a characteristic of the source of the light and is thus unaffected by the change in medium</p>
<p>I understand the frequency doesn't change, but how would that help me to solve the problem? I'm not sure if my equations are right but for "a" i used v=c/n to find the speed of the blue light in the glass. For "b" i used lambda of medium=lambda of light/n. For "c" i found the velocity of red light the same way I did in part "a" and plugged that into f=v/lambda (lambda would be the answer I found in part "b"). Does this sound right to you?</p>
<p>you just got me confused. but here's what i was thinking before,
n=c/v. all light (color doesnt matter) travel at c in a vacuum. so you can find v. f=c/lamda (the lamda is the original lamda, so for red light, its 700nm) since f doenst change in different medium. then using the v that you found and f, you can calculate the new lamda.</p>