1. Light Waves
Sec 1

2. Light Waves Strike objects
Reflected
Absorbed
Transmitted

3. Properties of objects
Opaque
Transparent
Translucent

4. Opaque
A material that reflects or absorbs all of the light that strikes it.

5. Transparent Material transmits light
Light passes through allowing you to see what is on the other side

6. Translucent Some light passes through
Material scatters light as the light passes through
You cannot see details

7. Reflection
Two kinds of wave reflection
Regular and
Diffused

8. Regular Reflection
Occurs when parallel rays of light hit a smooth surface
All the rays are reflected at the same angel

9. Diffuse Reflection
When parallel rays of light hit a bumpy, or uneven surface
The rays are reflected at different angels

10. Mirrors Sheet of glass Smooth, silver-colored coating
When light passes through the mirror, the back coating causes the light to reflect regularly, allowing you to see an image

11. Image
Is a copy of an object formed by reflected or refracted rays of light

12. Plane Mirror Flat mirror Produces a image that is right-side up and
The same size as the object being reflected

13. Virtual Image
The image you see when you look in a plane mirror is a virtual image
Right-side up or upright

14. Concave Mirrors Surface curves inward
Can form virtual images, real images, or no image
Depends on position of the object in relation to the focal point

15. Real Image Formed when rays actually meet at a point
The images are upside down, or inverted

16. Focal Point
The point at which the rays meet

17. Convex Mirrors A mirror with a surface that curves outward
Images are always virtual

18. Refraction and Lenses
Sec 2

19. Index of refraction
measure of how much a ray of light bends when it enters that material

20. Mirages Is an image of a distant object caused by refraction of light
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21. Concave lens
Is thinner in the center than at the edges

22. Convex lenses
Is thicker in the center than at the edges

23. Color
Sec 3

24. Color The color of an object is the color of light it reflects
White=reflects all colors
Black= absorbs all colors

25. Primary Colors Three colors that can be used to make any other color
Red, green, and blue
Any two primary combined in equal amounts produce a secondary color

26. Seeing Light Waves
Sec 4

27. The Eye
Organ System
Each part plays an important part in helping you see

28. Cornea Light enter the eye through this transparent surface
The cornea protects the eye
It also acts as a lens bending light waves as they enter the eye

29. Iris Is a ring of muscle that contracts and expands
This changes the amount of light that enter the eye
Also give the eye color

30. Pupil
Looks black
As light dims, the pupil enlarges allowing in more light
Vis versa

31. Lens
Behind the pupil
Refracts light, forming and image
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32. Retina Layer of cells lining the inside of the eye
Contains many of tiny, light-sensitive cells called, rods and cones

33. Rods Rods contain pigments that react to small amounts of light
Important for seeing at night

34. Cones Respond to color Three types: red, blue, and green
Function with bright

35. Optic Nerve
The signals generated by the rods and cones travel to the brain along a short, thick nerve
The brain turns the image right-side up

36. Correcting Vision Lenses in glasses are either concave or convex
The type of lens used depends on whether the eye is too long or too short

37. Nearsightedness
Person can see nearby things clearly, but objects at a distance appear blurry
Eyeball is a little to long
Concave lens correct this

38. Farsightedness
Person can see far away, but objects nearby appear blurry
Eyeball is too short
This is corrected with convex lenses