1. Overview of the course Principles of geometric optics
Physics 123, Spring, 2005
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2. Introduction Instructor Prof. Regina Demina Office B&L 313
Phone
Office hour Mon 4-5 pm
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3. Novosibirsk
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4. Objective of the course
thorough understanding of the basic physics concepts
ability to use them in applications
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5. Sources Text book Physics for Scientists and Engineers, Volume II
Third Edition
by Douglas C. Giancoli
Class web site /
Lecture notes;
Homework assignments, numeric answers, solutions
Equation sheets for tests, test solutions
Important dates and links
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6. Recitations and Homework
Solving problems systematically is important.
Difference with PHY122: no more workshops recitations
Recitations will cover material through the Wednesday lecture.
Participation in recitations will count 10% of your final grade. Grade assigned by your TA.
Recitations start the week of 1/18, sign up will be open on Thursday 01/13:
Homework is due in recitation class.
Homework problems = 10% of your final grade.
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7. One –hour exams There will be two one-hour exams during the semester.
Both will count.
There will be no makeup exam.
Exams will be given in Wednesday lecture class shown in the schedule. Exam dates are subject to change. I will notify you by in case of change.
You can bring a calculator, a pencil and a ruler.
40% of your grade.
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8. Final Exam Tuesday, May 3, 8:30 am (sorry!)
Final exam is based on the entire course PHY123.
Last homework will be based on the entire course to give you more time to prepare for the final. It will not be graded.
30% of the final grade
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9. Equation sheets No notes or equation sheets may be brought to exams.
However, a sheet of useful equations will be provided during the test. You can view these sheets in advance, will be linked from course schedule on the web.
Please note that past experience has shown that having equations available does not guarantee success -- understanding is the key.
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10. Labs The laboratory is a required and integrated part of the course.
A passing grade in laboratory is required to pass the course: 10% of the grade
Lab manuals and sign up are available on the web:
See the lab manual for rules and grading procedures.
Start sign up this week (you will be notified by , but you need to be registered for lab class!!)
Important: There is a short homework (in manuals) due at the beginning of each lab class (even the 1st one!!!) You will not be allowed to start your lab without this homework.
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11. Grading Workshops: 10% Homework: 10% Hour Exams: 40% Final Exam: 30%
Laboratory: 10%
Total: %
90% or above: A – A – B+
80% - 85% : B – B – C+
70% - 75%: C – C – D+
60% - 65%: D
Under 60% : F
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12. Phys 121123
Phys 121
how do objects move (kinematics)
Why do objects move (dynamics – forces)
One true (fundamental) force – gravity
First step into the micro world – kinetic theory
Phys 122
Two more true forces – electricity and magnetism
Unification – EM waves – light
Phys 123
More detailed study of light
Geometric optics wave properties  particle properties  Quantum mechanics (lasers)  space-time properties
Deeper into the structure of matter – atomic structure
Nuclear structure, elementary particles
Way out in space - cosmology
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13. Principles of geometric optics
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14. Concepts Ray model of light Image formation Reflection Refraction
Dispersion
Total internal reflection
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15. EM waves c – speed of light (m/s) f – frequency (Hz=1/s)
l – wavelength (m)
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16. Ray model of light
Light is an EM wave diffraction (go around obstacles)
This happens on microscopic scale
In everyday life we use straight line approximation for light propagation = Ray model of light  geometric optics
We infer positions of objects assuming light travels in straight lines.
Geometry is important,
Bring ruler and pencil,
make good pictures!!!
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17. Reflection We see objects because
They emit light (Sun, light bulb)
They reflect light (Moon, table)
angle of incidence = angle of reflection:
qi=qr
Rough surface Polished surface.
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18. Formation of image
Eye assumes light propagates in straight lines  image (rays of light crossing) is formed behind the mirror
do – distance to object
di – distance to image
For plane mirror
do= di
No light here
 Virtual image
If light actually goes through the place
where image is formed  real image
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19. Speed of light in medium
Speed of light in vacuum:
c=3.0x108m/s
Speed of light in media:
v<c
Index of refraction:
n=c/v >1.0
From table 33-1
Vacuum n=1.00
Air n=1.0003
Water n=1.33
Diamond n=2.42
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20. Refraction
The front is slowing down
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21. Refraction, Snell’s law
Bend toward normal
Bend away from normal
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22. Image formation
Eye still assumes light propagates in straight lines  optical illusions
Image is shifted
Pool appears shallower
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23. What if n depends on l?
If n depends on l  angle of refraction depends on l
n(red)<n(green)
A-red, B-green
B- red, A-green A B
Dispersion
This is why rainbow occurs
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24. Total internal reflection
For q>qc - total internal reflection –
no light come out – all light is reflected
Fiber optics
Necessary condition:
from thick to thin media
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25. 1.3 m
2.1 m
2.7 m x
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