an introduction to refraction snc2d. index of refraction light will travel more slowly in more dense...
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![Page 1: An Introduction to Refraction SNC2D. Index of Refraction Light will travel more slowly in more dense materials. The ratio of the speed of light in a vacuum](https://reader035.vdocuments.mx/reader035/viewer/2022062618/55145e8e550346494e8b57d5/html5/thumbnails/1.jpg)
An Introduction to Refraction
SNC2D
![Page 2: An Introduction to Refraction SNC2D. Index of Refraction Light will travel more slowly in more dense materials. The ratio of the speed of light in a vacuum](https://reader035.vdocuments.mx/reader035/viewer/2022062618/55145e8e550346494e8b57d5/html5/thumbnails/2.jpg)
Index of Refraction
Light will travel more slowly in more dense materials. The ratio of the speed of light in a vacuum (or air) to the speed in the material is the index of refraction (or refractive index), n.
nc
v
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Index of Refraction: Example
For water, the index of refraction is 1.33. The speed of light in water is therefore:
?:
100.3
33.1:8
vR
c
nG
sm
![Page 4: An Introduction to Refraction SNC2D. Index of Refraction Light will travel more slowly in more dense materials. The ratio of the speed of light in a vacuum](https://reader035.vdocuments.mx/reader035/viewer/2022062618/55145e8e550346494e8b57d5/html5/thumbnails/4.jpg)
Index of Refraction: Example
For water, the index of refraction is 1.33. The speed of light in water is therefore:
n
cv
v
cnA :
?:
100.3
33.1:8
vU
c
nG
sm
![Page 5: An Introduction to Refraction SNC2D. Index of Refraction Light will travel more slowly in more dense materials. The ratio of the speed of light in a vacuum](https://reader035.vdocuments.mx/reader035/viewer/2022062618/55145e8e550346494e8b57d5/html5/thumbnails/5.jpg)
Index of Refraction: Example
For water, the index of refraction is 1.33. The speed of light in water is therefore:
sms
m
vS
n
cv
v
cnS
88
103.233.1
100.3:
:
?:
100.3
33.1:8
vU
c
nG
sm
![Page 6: An Introduction to Refraction SNC2D. Index of Refraction Light will travel more slowly in more dense materials. The ratio of the speed of light in a vacuum](https://reader035.vdocuments.mx/reader035/viewer/2022062618/55145e8e550346494e8b57d5/html5/thumbnails/6.jpg)
Frequency and Wavelength
Since the wave slows down but the frequency remains the same (the frequency of a wave is always the frequency of the source), the wavelength gets shorter. f
vfv
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Boundaries
So in 2D (with the boundary at an angle to the wave), the wave will bend as those parts that enter the more-dense material first slow down first.
(The black lines show the crests or “wavefronts”).
![Page 8: An Introduction to Refraction SNC2D. Index of Refraction Light will travel more slowly in more dense materials. The ratio of the speed of light in a vacuum](https://reader035.vdocuments.mx/reader035/viewer/2022062618/55145e8e550346494e8b57d5/html5/thumbnails/8.jpg)
Please Note!
If the ray is perpendicular to the boundary, no bending will occur:
![Page 9: An Introduction to Refraction SNC2D. Index of Refraction Light will travel more slowly in more dense materials. The ratio of the speed of light in a vacuum](https://reader035.vdocuments.mx/reader035/viewer/2022062618/55145e8e550346494e8b57d5/html5/thumbnails/9.jpg)
Snell’s Law
The amount by which the wave is bent is given by Snell’s Law (ni and nr are the refractive indices of the media).
n ni i r rsin sin
![Page 10: An Introduction to Refraction SNC2D. Index of Refraction Light will travel more slowly in more dense materials. The ratio of the speed of light in a vacuum](https://reader035.vdocuments.mx/reader035/viewer/2022062618/55145e8e550346494e8b57d5/html5/thumbnails/10.jpg)
Snell’s Law
Note that a ray will always bend towards the normal when travelling into a more-dense medium
![Page 11: An Introduction to Refraction SNC2D. Index of Refraction Light will travel more slowly in more dense materials. The ratio of the speed of light in a vacuum](https://reader035.vdocuments.mx/reader035/viewer/2022062618/55145e8e550346494e8b57d5/html5/thumbnails/11.jpg)
Snell’s Law
Note that a ray will always bend towards the normal when travelling into a more-dense medium (and away from the normal when travelling into a less-dense medium).
![Page 12: An Introduction to Refraction SNC2D. Index of Refraction Light will travel more slowly in more dense materials. The ratio of the speed of light in a vacuum](https://reader035.vdocuments.mx/reader035/viewer/2022062618/55145e8e550346494e8b57d5/html5/thumbnails/12.jpg)
Problem Solving with Snell’s Law
When light passes from air into water at an angle of 45o from the normal, what is the angle of refraction in the water?
![Page 13: An Introduction to Refraction SNC2D. Index of Refraction Light will travel more slowly in more dense materials. The ratio of the speed of light in a vacuum](https://reader035.vdocuments.mx/reader035/viewer/2022062618/55145e8e550346494e8b57d5/html5/thumbnails/13.jpg)
Problem Solving with Snell’s Law
When light passes from air into water at an angle of 45o from the normal, what is the angle of refraction in the water?
?:
45
33.1
0.1:
water
air
water
air
U
n
nG
![Page 14: An Introduction to Refraction SNC2D. Index of Refraction Light will travel more slowly in more dense materials. The ratio of the speed of light in a vacuum](https://reader035.vdocuments.mx/reader035/viewer/2022062618/55145e8e550346494e8b57d5/html5/thumbnails/14.jpg)
Problem Solving with Snell’s Law
When light passes from air into water at an angle of 45o from the normal, what is the angle of refraction in the water?
?:
45
33.1
0.1:
water
air
water
air
U
n
nG
![Page 15: An Introduction to Refraction SNC2D. Index of Refraction Light will travel more slowly in more dense materials. The ratio of the speed of light in a vacuum](https://reader035.vdocuments.mx/reader035/viewer/2022062618/55145e8e550346494e8b57d5/html5/thumbnails/15.jpg)
Problem Solving with Snell’s Law
When light passes from air into water at an angle of 45o from the normal, what is the angle of refraction in the water?
?:
45
33.1
0.1:
water
air
water
air
U
n
nG
water
airairwater
waterwaterairair
n
n
nnS
sin
sin
sinsin:
![Page 16: An Introduction to Refraction SNC2D. Index of Refraction Light will travel more slowly in more dense materials. The ratio of the speed of light in a vacuum](https://reader035.vdocuments.mx/reader035/viewer/2022062618/55145e8e550346494e8b57d5/html5/thumbnails/16.jpg)
Problem Solving with Snell’s Law
When light passes from air into water at an angle of 45o from the normal, what is the angle of refraction in the water?
?:
45
33.1
0.1:
water
air
water
air
U
n
nG
water
airairwater
waterwaterairair
n
n
nnS
sin
sin
sinsin:
![Page 17: An Introduction to Refraction SNC2D. Index of Refraction Light will travel more slowly in more dense materials. The ratio of the speed of light in a vacuum](https://reader035.vdocuments.mx/reader035/viewer/2022062618/55145e8e550346494e8b57d5/html5/thumbnails/17.jpg)
Problem Solving with Snell’s Law
When light passes from air into water at an angle of 45o from the normal, what is the angle of refraction in the water?
?:
45
33.1
0.1:
water
air
water
air
U
n
nG
water
airairwater
waterwaterairair
n
n
nnS
sin
sin
sinsin:
32)53166.0(sin
53166.033.1
45sin)0.1(sin:
1water
waterS
![Page 18: An Introduction to Refraction SNC2D. Index of Refraction Light will travel more slowly in more dense materials. The ratio of the speed of light in a vacuum](https://reader035.vdocuments.mx/reader035/viewer/2022062618/55145e8e550346494e8b57d5/html5/thumbnails/18.jpg)
Dispersion
Note that since different wavelengths of white light refract slightly differently, refraction can split white light into its different wavelengths (i.e. colours) especially if refracted twice.
![Page 19: An Introduction to Refraction SNC2D. Index of Refraction Light will travel more slowly in more dense materials. The ratio of the speed of light in a vacuum](https://reader035.vdocuments.mx/reader035/viewer/2022062618/55145e8e550346494e8b57d5/html5/thumbnails/19.jpg)
Dispersion
Note that since different wavelengths of white light refract slightly differently, refraction can split white light into its different wavelengths (i.e. colours) especially if refracted twice.
![Page 20: An Introduction to Refraction SNC2D. Index of Refraction Light will travel more slowly in more dense materials. The ratio of the speed of light in a vacuum](https://reader035.vdocuments.mx/reader035/viewer/2022062618/55145e8e550346494e8b57d5/html5/thumbnails/20.jpg)
Dispersion
Note that since different wavelengths of white light refract slightly differently, refraction can split white light into its different wavelengths (i.e. colours) especially if refracted twice.
This is called dispersion.