2. Light travels in straight lines.
We can illustrate this by using “light rays”
Light rays:
Using light rays to determine how light behaves is called “geometric
optics”
LIGHT AND MIRRORS
3. 3 types of matter that light encounters…
Transparent Translucent Opaque
LIGHT AND MIRRORS
4. 2 types of light…
Incident light Reflected light
Reflective surface
LIGHT AND MIRRORS
5. Angle of
incidence
Angle of
reflection
1) The angle of incidence equals
the angle of reflection
2) The incident ray, the reflected
ray, and the normal all lie in the
same plane
∠i = ∠r
LAWS OF REFLECTION
10. LAWS OF REFLECTION
The word “AMBULANCE” appears backwards in real life, but proper in a
reflection.
11. 1) Specular reflection
Reflection off a smooth surface
2) Diffuse reflection
Reflection off an irregular/dull
surface
REFLECTING LIGHT OFF SURFACES
12. - Too much glare off white
paper (too much reflected
light)
- Contrast between black text
and white paper is too high
- Use colour filters/glasses to
reduce glare
REFLECTION AND DYSLEXIA
14. Virtual image: An image in which light does not actually arrive at
or come from the image location
Virtual image
USING LIGHT RAYS TO SEE AN OBJECT
15. Step 1
Identify the top and the bottom of the object
(label these “A” and “B”)
USING LIGHT RAYS TO SEE AN OBJECT
16. • Draw a line from point A that is perpendicular to the mirror
Step 2
USING LIGHT RAYS TO SEE AN OBJECT
17. • Draw an incident ray (starting at
point A)
• Draw a “normal” where the
incident ray hits the mirror
• Use a protractor to draw a
reflecting ray
(Remember that ∠i = ∠r )
Step 3
USING LIGHT RAYS TO SEE AN OBJECT
18. • Extend line A to point Ai (equidistant from point A on the other
side of the mirror)
• Connect point Ai to your reflection ray
USING LIGHT RAYS TO SEE AN OBJECT
Step 4
19. • Repeat steps 2-4 for Point B
USING LIGHT RAYS TO SEE AN OBJECT
Step 5
