Reflection and Image Formation

1
Section 17.1 and 4

• Reflection and Image Formation

2
Reflection

• What is reflection?

3
Reflection
http//www.glenbrook.k12.il.us/gbssci/phys/Class/r
efln/u13l1d.html

• What is the Law of Reflection?

4
Reflection
http//www.glenbrook.k12.il.us/gbssci/phys/Class/r
efln/u13l1d.html

• For what angles does the law hold true?
• Does it matter at what angle the surface is held?
  

5
Reflection
http//www.glenbrook.k12.il.us/gbssci/phys/Class/r
efln/u13l1d.html

• What happens when light rays reflect off an
  uneven surface?

6
Reflection
http//www.glenbrook.k12.il.us/gbssci/phys/Class/r
efln/u13l1d.html

• Why is it so hard to see the on rainy nights,
  especially the road?

7
Mirrors

• Types of Mirrors

8
Mirrors

• What is an image?

9
Mirrors

• Where are the images located?

10
Mirrors

• Parts to a mirror
• Focal Point (F)
• Center of Curvature (C)

11
Mirrors

• Ray Diagrams
• Three rules for drawing them
• Light in parallel will reflect out through the
  focal point.
• Light in through the focal point will reflect out
  parallel
• If rays do not meet, trace them behind the
  mirror.

12
Mirrors

• Plane Mirrors

13
Mirrors

• Concave (in between C and F)

14
Mirrors

• Concave (at F)

15
Mirrors

• Concave (Beyond C)

16
Mirrors

• Concave (between F and mirror)

17
Mirrors

• Convex

18
Mirrors

• Describing the Images

19
Mirror

• Object and Image Distances

20
Mirror Example 1

• With his face 6.0 cm from the bottom of an empty
  bowl, Spot sees his reflection 12 cm behind the
  bowl and jumps back. Describe the image that Spot
  saw. Find the focal point of the bowl.

21
Mirror Example 2

• A friend is wearing a pair of mirrored sunglasses
  whose convex surface has a focal length of 20.0
  cm. If your face is 40.0 cm from the sunglasses,
  how far behind the sunglasses is your image?

22
Mirror Example 3

• A colored reflecting sphere was a popular lawn
  ornament. If a bird is 13.4 cm from the sphere
  and sees its image reflected 8.6 cm behind the
  sphere, where is the focal point? Describe the
  image seen by the bird.

23
Mirror Example 4

• Make up mirrors tend to be concave mirrors.
  Marissa has one with a focal point of 18 cm. If
  she looks into it from a distance of 12 cm, how
  far is her image from the mirror? Is Marissa's
  location important when looking in the mirror?

24
Section 17.1 and 3 Homework

• Read Section 17.1 and 3
• Answer Questions 1-8, 22-27
• Complete exercises 1, 10-13
• Homework Check will be Friday
• Article Due June 1st, on Reflection or Refraction
• Chapter 16 and 17 test on Wednesday, June 3rd.