Angle between colors - dispersion

  • Thread starter Thread starter BDR
  • Start date Start date
  • Tags Tags
    Angle Dispersion
Click For Summary

Homework Help Overview

The discussion revolves around a problem involving the dispersion of light as it transitions from polystyrene to air, specifically focusing on the yellow and green wavelengths of light. The participants are exploring the application of Snell's Law to determine the angle between the two colors upon emergence.

Discussion Character

  • Exploratory, Assumption checking, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss the use of Snell's Law for calculating the angles of refraction for different wavelengths. There are questions about the correctness of calculations and the need for refractive indices specific to each wavelength.

Discussion Status

Some participants have provided guidance on the calculations, suggesting steps to solve for the angles of refraction and how to find the angle between the two colors. There is an ongoing exploration of potential errors in calculations, but no consensus has been reached regarding the correct approach or results.

Contextual Notes

There is an emphasis on the need for accurate refractive indices for the specific wavelengths involved, and the original poster expresses uncertainty about their calculations without providing detailed workings. The expected outcomes are mentioned, but the discussion remains focused on the process rather than the results.

BDR
Messages
13
Reaction score
0
(a) A narrow beam of light containing yellow (660nm) and green (550nm) wavelengths goes from polystyrene to air, striking the surface at a 30 degree incident angle. What is the angle between the colors when they emerge? (b) How far would they have to travel to be separated by 1.00 mm?

I need some guidance on if i am working the problem right! Do i use Snell's Law?

1.49sin30 = 1.000293sin(angle)?
 
Physics news on Phys.org
Yes, use Snell's law of refraction. But you need to know the refractive index for each wavelength. The angle of incidence is the same (30 degrees), but the angle of refraction will be slightly different for each wavelength.
 
Here is what I'm doing!

Yellow: 1.492sin(30) = 1.000293sinθ

Green: 1.493sin(30) = 1.000293sinθ

When I do the calculations i am not getting the correct. The answer is suppose to be 0.043 degrees and 1.33 m. Where do you think I am messing up the calculations?
 
Beats me since you didn't show your calculations!

Using those same equations I get 0.043 degrees, so I'm not sure where you went wrong. Try this: (1) Solve for the angle of refraction for each color; (2) Subtract those angles to find the angle between the two refracted colors.
 

Similar threads

Replies
10
Views
8K
  • · Replies 207 ·
7
Replies
207
Views
16K
Replies
1
Views
2K
Replies
2
Views
2K
  • · Replies 7 ·
Replies
7
Views
6K
  • · Replies 9 ·
Replies
9
Views
3K
  • · Replies 1 ·
Replies
1
Views
12K
  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 9 ·
Replies
9
Views
3K
Replies
1
Views
5K