presentation

1. W. Sautter 2007

2. The next slide is a quick promo for my books
after which the presentation will begin
Thanks for your patience!
Walt S.
Wsautter@optonline.net
More stuff at: www.wsautter.com

3. Walt’s Books for Free!
Books available at:
www.wsautter.com
www.smashwords.com
www.amazon.com
www.bibliotastic.com
www.goodreads.com

4. Normal
Line
qi
qi = angle of incidence
Normal
Line
qi
qr
qr
Glass
n = 1.5
Air
n =1.0
qr = angle of refraction
Light travels more slowly
in glass than air and
bends towards the normal
when entering glass from air
Light moving from
glass to air
increases speed
and bends away
from the normal

5. Virtual focus
Focus = -
Can form only virtual,
Erect and reduced
images

6. Principle
focus
Parallel rays
Focus = +
Can form real images
(enlarged or reduced
& inverted) or
Enlarged virtual images

7. Normal
Line
q qr i
Incident
ray
Reflected
ray
Mirror surface
Angles are ALWAYS measured from the NORMAL LINE

8. Real
Focus
Parallel rays
Reflected rays
Focal length = +
Forms real, inverted,
Reduced or enlarged
Image. Also forms
Virtual, erect,
Enlarged images.

9. Parallel rays
Reflected rays
Virtual focus
Focal length = -
Forms only virtual,
erect, reduced
images between
the virtual focus
and the mirror.

10. Waves from a
Distant source
= crest
= trough
Barrier with
Two slits
Destructive
interference
Constructive
interference
In phase waves
Emerge from slits

11. Wavelength
l
Frequency
n
Velocity Wavelength
l
Frequency
n
Velocity
x = v

12. VISIBLE AND INVISIBLE LIGHT
• MOST “LIGHT” IS NOT VISIBLE TO THE HUMAN EYE !
• ONLY ABOUT 7 % OF THE KNOWN KINDS OF LIGHT
CAN BE SEEN WITHOUT SPECIAL INSTRUMENTATION.

13. THE PHOTOELECTRIC EFFECT EXPERIMENT
ONLY CERTAIN MINIMUM FREQUENCIES OF LIGHT
POTASSIUM METAL
VOLTMETER
BATTERY
PHOTONS
PICKUP
WIRE
ELECTRONS
FREE THE ELECTRONS FROM THE METAL
(ONLY PHOTONS WITH ENOUGH ENERGY)

14. Parallel ray
Focal ray
Ray thru 2f
2 f focus (f)
vertex
Reflects thru
The focus
Principal axis
Reflects parallel
To principal axis
Reflects Back
Into itself

15. Parallel ray
Focal ray
Object beyond 2f
Ray thru 2f
2 f f
Image is:
Real
Inverted
Reduced
Appears between f & 2f

16. Image is:
Real
Inverted
Same size
Appears at 2f
Parallel ray
Focal ray
Object at 2f
ray thru 2f 2 f f

17. Image is:
Real
Inverted
Enlarged
Appears beyond 2f
Object between
f and 2f
Parallel ray
ray thru 2f
Focal ray
2 f f

18. Parallel ray
Image is:
Virtual
Erect
Enlarged
Appears behind the
mirror
ray thru 2f
Focal ray
2 f f
ray thru 2f
Apparent
Convergence
Of rays
Object inside
focus

19. Angle of incidence = Angle of Reflection
For each ray
Dotted lines
Shows the
Apparent
Ray source

20. Parallel rays
Reflected rays
Virtual focus
Dotted lines
Shows the
Apparent
Ray focus
Focal length = -
Forms only virtual,
erect, reduced
images between
the virtual focus
and the mirror.

21. Apparent
Convergence of rays
(f) 2 f
Parallel ray
Ray thru 2f
Focal ray
Image is:
Virtual
Erect
Reduced
Appears behind the
mirror

22. Parallel ray
Passes thru
The focus
2 f focus (f) focus (f) 2 f
x x x x
Focal ray
Refracts parallel
To principal axis
A ray thru the
Center of the
lenses
Remains
unbent

23. Parallel ray
2 f focus (f) focus (f) 2 f
x x x x
Focal ray
Image is:
Real
Inverted
Reduced
Appears between
f and 2f
Object beyond 2f

24. Parallel ray
2 f focus (f) focus (f) 2 f
x x x x
Focal ray
Image is:
Real
Inverted
Same size
Appears between
f and 2f
Object at 2f

25. Parallel ray
2 f focus (f) focus (f) 2 f
x x x x
Focal ray
Image is:
Real
Inverted
Enlarged
Appears beyond 2f
Object between
f and 2f

26. Image is:
Virtual
Erect
Enlarged
Appears on same
Side as Object
Apparent
Convergence
Of rays
2 f focus (f) focus (f) 2 f
x x x x
Object
Inside
focus

27. 2 f focus (f) focus (f) 2 f
Apparent ray convergence
Is on same side as object

28. Focal ray
Parallel ray
2 f f f 2 f
Ray thru center
Image is:
Virtual
Erect
Reduced
Appears on same
Side as object

29. Wave A
Wave A
Wave A
Wave B
Wave B
Wave B
Constructive interference
Destructive interference
Partially Constructive
interference

30. Waves from a
Distant source
= crest
= trough
Barrier with
Two slits
Destructive
interference
Constructive
interference
In phase waves
Emerge from slits

32. l q

33. d
l
2
1
0
1
2
m
SPECTRAL
ORDER
q

34. m = spectral order
The bright central band is zero and each bright band
to the right or left is counted by consecutive
integers 1,2,3 etc.
d = distance separating the slits (meters)
l= wavelength of light in meters
q = angle between the zero band and the spectral band m

35. Each edge of the slit creates
a new wave front. The
two new waves then interfer
creating a diffraction pattern

36. l q
m = spectral order
The bright central band is zero and each dark band
to the right or left is counted by consecutive
integers 1,2,3 etc.
s= slit width (meters)
l= wavelength of light in meters
q = angle between the zero band and the spectral band m