Download Light and optics

Physics of Astronomy
Spring 2006
Astronomy & Astrophysics
Electromagnetism
Seminar: Cosmology & Journals
Your research
Today: short course on LIGHT
When shall we have weekly research reports?
Mondays after HW session?
Seminar
Electromagnetism
• Giancoli = primary source
• New! Workshop Physics Module 4 by Laws
(Dickinson) on reserve in Library
• Copy or order Workshop Physics
Light (today)
Potentials (next week)
Circuits through Maxwell’s equations
□ Look at SYLLABUS together…
Light
Ch.33 Reflection & Refraction
Ch.34 Lenses & optical instruments
Ch.35 Interference
Ch.36 Diffraction & Polarization
Hitting the high points….
Ch.33 Reflection
Images formed in mirrors
1
dobject

1
dimage
1

f
Refraction: v = c/n; n1sinq1 = n2sinq2
Q.13
Refraction
Total internal reflection
Ch.34 Lenses & optical instruments
1
dobject

1
dimage
1

f
Object far from converging lens forms real image near focal point.
Object close to converging lens forms virtual image.
Combinations of lenses
(1) Find location of Image 1 → (2) Let this be Object 2 → Find Image 2
Simple camera and human eye
Corrective lenses
Magnifying glass
Telescope
Ch.35 Interference
Huyghen’s principle
Every point on a wave front
can be considered as a
source of tiny wavelets that
spread our in the forward
direction at the speed of the
wave itself.
Huyghens explains refraction
Interference – Young’s double-slit experiment
□ First, PREDICT PATTERNS if light is PARTICLES or WAVES
Interference – theoretical explanation
Interference bright spots
d sin q  m
Ch.36 Diffraction & Polarization
Diffraction through a single slit
Diffraction DARK spots at
a sin q  m
Diffraction through a double slit
Diffraction grating
Resolution limits
1.22 
q
D
Polarization
Polarization by reflection
n2
tan q p 
n1