Unit 3 Optics: Chapter 5
Law of Reflection
To show how light is _______________________________ from a solid surface, we can use ray
diagrams. A ray diagram has 5 main components:
1. __________________________________________________________:
_____________________________________________________________________________________________
_____________________________________________________________________________________________
2. __________________________________________________________:
_____________________________________________________________________________________________
_____________________________________________________________________________________________
3. __________________________________________________________:
_____________________________________________________________________________________________
_____________________________________________________________________________________________
4. __________________________________________________________:
_________________________________________________________________________________________
_________________________________________________________________________________________
5. __________________________________________________________:
_____________________________________________________________________________________________
_____________________________________________________________________________________________
YOU HAVE TO DRAW THIS!
*__________________________________________________________:
_____________________________________________________________________________________________________
Recall:
_______________________________________________________ (reflection from a mirror-like surface)
 ________________________________________________________________________________
 For a surface to act as a mirror and produce _____________________________
reflection, it must be _______________________ compared to the
wavelength of the light striking the surface.
YOU HAVE TO DRAW THIS!
_____________________________________________________________ (reflection from a rough surface).
 No clear image produced, but you can see the surface the light is bouncing
off.
 Light bounces off in random directions
 Example: A piece of paper (the black ink absorbs all the light and the white
paper reflects all the light in random directions )
YOU HAVE TO DRAW THIS!
How Do We Use Specular and Diffuse Reflection Everyday?
 _________________________________________________________________________________________
 _________________________________________________________________________________________
 _________________________________________________________________________________________
 _________________________________________________________________________________________
 _________________________________________________________________________________________
 _________________________________________________________________________________________
 _________________________________________________________________________________________
Types of Mirrors
1. ______________________________________________________:
_________________________________________________________________________________________
_________________________________________________________________________________________
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2. ______________________________________________________:
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
3. ______________________________________________________:
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________
Examples:
Plane: ________________________________________________________________________________
Concave: _____________________________________________________________________________
Convex: ______________________________________________________________________________
Images in a Plane Mirror
The angle of incidence and the angle of reflection are always ___________________________
(law of reflection).
The image and the object distance from the mirror are always _________________________.
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Ray diagram of a Plane Mirror (Page 189)
***Core Lab Page 192***
Images in Concave Mirrors
Reflected light rays travel __________________________________________________________________.
_______________________________:
________________________________________________________________________________
_______________________________:
________________________________________________________________________________
If you then draw rays of light approaching the mirror parallel to the principal axis,
you will see that all of the reflected rays intersect at one point.
This is the ____________________________________________________________________________________.
Ray diagrams for Concave Mirrors
 Object is between Focal point and Mirror (See Page 198)
The image will be …
1.
2.
3.
4.
Size
Position
Orientation (upright/inverted)
Type of image (Real/virtual)
4
YOU TRY IT!!!
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
1.
2.
3.
4.
Object is between the focal point and 2X the focal length. (See Page 200)
The image will be …
Size
Position
Orientation (upright/inverted)
Type of image (Real/virtual)
YOU TRY IT!
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
Object is beyond 2X the focal length. (See Page 202)
The image will be …
1.
2.
3.
4.
Size
Position
Orientation (upright/inverted)
Type of image (Real/virtual)
YOU TRY IT!
 Textbook: page 202 #'s 1-2
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Images in Convex Mirrors
Reflected rays __________________________________________________. But, if you extend the
rays _______________________________ the mirror, the extended rays will intersect at the
________________________________________________________, F.
The focal point for a convex mirror is _____________________________________________.
Ray diagrams for Convex Mirrors
When drawing ray diagrams for a convex mirror, you follow the same steps no
matter where the object is in relation to the mirror (the object distance doesn’t
matter).
Remember in convex mirrors the focal point is always BEHIND THE MIRROR.
See Page 205
1.
2.
3.
4.
The image will be …
Size
Position
Orientation (upright/inverted)
Type of image (Real/virtual)
YOU TRY IT!
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***Textbook: page 206 #'s 1-3***
Summary:
There are two types of curved mirrors:
1) ______________________________________________ have a reflective surface that curves
inward. Depending on the location of the object relative to the focal point of
the mirror, images in these mirrors can be:
1) ______________________ or ____________________________ ( a real image is
formed when reflected rays meet).
2) ______________________ or _____________________________
3) ____________________________ or _______________________ than the object
2. ______________________________________________ have a reflective surface that
curves outward. Images in convex mirrors are:
1. ________________________________________________________________________________
2. ________________________________________________________________________________
3. ________________________________________________________________________________
4. ________________________________________________________________________________
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WHAT WILL IT LOOK LIKE! (SPOT)
Mirror/Object
type
Size
Position
Orientation
Type
Concave mirror
(Object
between focal
point and
mirror)
Concave Mirror
(Object
between focal
point and two
times the focal
length)
Concave mirror
(Object beyond
two times the
focal length)
Convex mirror
Real Vs. Virtual Images
 Describe the difference between real and virtual images. Use your notes and
your textbook:
_________________________________________________________________________________________________
_________________________________________________________________________________________________
_________________________________________________________________________________________________
_________________________________________________________________________________________________
_________________________________________________________________________________________________
_________________________________________________________________________________________________
P. 187, #s 2, 7a, 9a&b, and 10; P. 209, #s 1-12
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