1. Reflection and Refraction
May 28, 2013

2. Objectives
1. Predict the path of reflected light striking a
reflective surface
2. Define virtual image
3. Give examples of refraction and describe
how it works

3. Law of Reflection
 The angle of reflection equals the angle of
incidence
– Angle of Incidence – the angle at which the
object hits a flat surface (i)
– Angle of Reflection – the angle at which it
rebounds off the flat surface (r)
– Normal – imaginary line that extends
perpendicular to the flat surface

5.  Flat mirrors – plane
mirrors show this
perfectly

6. Virtual Images
 When you look at a mirror it appears that
you are behind that mirror in exactly the
same position
 It is the reflection that we see, but our minds
perceive it not as a reflection, but as coming
out from the mirror

9. Curved mirrors
 Law of Reflection still holds, but the sizes
and distance of the object and image are
not equal
 Convex mirror – curves outward, virtual
image is smaller and closer
 Concave mirror – curves inward, virtual
image is larger and further away

10.  What evidence can you use to support the
claim that the frequency of light does not
change upon reflection? (pg. 255)
 If you took a picture of your image while
standing 2 m in front of a plane mirror, what
distance should you set your camera to
provide the sharpest focus? (pg. 255)

11. Diffuse Reflection
 Light incident on a rough surface reflects in
many directions

12. Refraction
 The bending of light due to changing speed,
passing from one medium to another

13.  When light slows down (goes into water) it
refracts toward the normal
 When light speeds up (goes into air) it
refracts away from the normal

14.  Why is it more dangerous to drive a car of a
rainy day? (pg. 257)
 If the speed of light were the same in all
media, would refraction still occur when light
passes from one medium to another? (pg.
258)