Lecture notes for a Modern Physics course using Giancoli.

1. Physics III: Quantum Physics
Modern Physics
NIST/JILA/CU-Boulder[NB]
G. H¨depohl/ESO[Hde]
o
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2. .
PHYS 283
Fundamentals of Physics III: Quantum
Physics
Lecture 1: Review of rays
.
M. Bellis
Department of Physics
Northern Illinois University
February 15, 2012
. . . . . .
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3. Outline
.
1 Announcements
.
2 Motivation
.
3 Review
Rays
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4. Announcements
• MasteringPhysics
• Review Chap 34 (reflection and refraction) and Chap 15 (waves).
• Reading for next class:
• Chap. 34-1, 34-2.
. . . . . .
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5. Announcements
• MasteringPhysics
• Review Chap 34 (reflection and refraction) and Chap 15 (waves).
• Reading for next class:
• Chap. 34-1, 34-2.
. . . . . .
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6. Announcements
• MasteringPhysics
• Review Chap 34 (reflection and refraction) and Chap 15 (waves).
• Reading for next class:
• Chap. 34-1, 34-2.
. . . . . .
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7. Soap bubble
Soap bubble[Gia08]. . . . . . .
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8. Rays
Relationship between rays and waves. Fig 15-20[Gia08] . . . . . .
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9. Rays
Law of reflection: the angle of reflection equals the
angle of incidence.
θr = θi
Figure: Fig. 15-21[Gia08]
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10. Rays
Law of refraction:
sin(θ2 ) v2
=
sin(θ1 ) v1
Why?
Figure: Fig. 15-28[Gia08]
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11. Principle of least action
Reflection minimizes distance traveled.
Verify this?
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12. Principle of least action
Refraction minimizes time traveled.
Verify this?
. . . . . .
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13. Principle of least action
Interactions proceed along a path that
minimizes a property called the action.
Principle of least action
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14. Principle of least action
Classic problem of lifeguard choosing a
path to the distressed swimmer.
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15. Rays
[Tra],[wik],[L.]
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16. Rays
[Tra],[wik],[L
. . . . . .
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17. Rays
[Tra],[wik],[L.]
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18. Rays
Ray tracing
Main tool of the computer-generated imagry
(CGI) industry.
Most CGI use this technique with rendering
farms.
Holy grail of the GPU/video game industry!
Try it yourself!
• http://www.povray.org/
• http://usa.autodesk.com/maya/
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19. Bibliography
Douglas C. Giancoli.
Physics for Scientists and Engineers.
4th edition, 2008.
G. Hdepohl/ESO.
http://www.eso.org/public/images/gerd_huedepohl_4/.
Greg L.
http://en.wikipedia.org/wiki/File:Ray-traced_steel_balls.jpg.
NIST/JILA/CU-Boulder.
http://patapsco.nist.gov/imagegallery/details.cfm?imageid=193.
Gilles Tran.
http://en.wikipedia.org/wiki/File:Glasses_800_edit.png.
http://en.wikipedia.org/wiki/File:BallsRender.png.
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