This document discusses reflection and mirrors. It begins by defining different types of reflection like regular and diffuse reflection. It then discusses the law of reflection and defines terms like normal. Several questions and explanations are provided about reflection in mirrors, including how big a mirror needs to be to see your full length, and why light from the sun or moon appears as a column when reflected off water. It is explained that a perfectly smooth water surface would reflect a round image, while roughness causes the image to appear smeared into a vertical column due to an assemblage of small mirror facets.

1. Reflection
Reflection off Paper Reflection off a M
irror
Regular Reflection
Diffuse Reflection

2. Law of Reflection

i


r
Normal - an imaginary lin
e drawn perpendicular to
the surface

3. Reflection

4. Reflections in a Mirror

5. Q

6. An observer observes a light source S in a mirror
. Where does he perceive the mirror image of S
to be located?
S
●1
●2
●3
●4

7. An observer observes a light source S in a mirror.
Where does he perceive the mirror image of S to b
e located?
S
●1
●2
●3
●4

8. How big does a mirror have to be in ord
er to see your entire length in it?
Half His Height!

9. To see more of her head in the mirror, she …
1. should hold the mirror closer
2. should hold the mirror farther away
3. needs a bigger mirror

12. Another way to
tell when you’re
dealing with so
meone who doe
s not have a gr
asp of even the
most rudimenta
ry concepts of
physics.

14. Why does light from the sun or moon appe
ar as a column when reflected from a body o
f water?
How would it appear if the water surface
were perfectly smooth?

15. If the water were perfectly smooth, a mirror image of the round s
un of moon would be seen in the water. If the water were slightly rou
gh, the image would be wavy. If the water were a bit more rough, littl
e glimmers of the sun or moon would be seen above and below the main
image.
This is because the water waves act like an assemblage of small fla
t mirrors. For rougher waves, there is a greater variety of mirror fac
ets properly tilted to reflect the light into your eye. The light then a
ppears smeared into a long vertical column.

19. Calmer Water
Calm Water

20. Very Calm Water Q