1. The bending of waves as they pass from one medium to another
Refraction
The bending of waves as they pass from one medium to another

2. Refraction

3. Refraction
The bending of light as it passes from one medium to another.
Dependent upon
Change in light wave speed
Change in direction
Bending means an abrupt change in direction.

4. Refraction—the cause
Waves change speed as they pass through different mediums
Mechanical waves travel fastest through solids, slowest through gases and not at all through space.
Electromagnetic waves (or light waves) travel fastest through space and slowest through (transparent or translucent) solids.

5. Refraction
The bending of light as it passes from one medium to another.
Dependent upon
Change in light wave speed
Change in direction
Bending means an abrupt change in direction.

6. For Light Waves
Light waves slow down as they move from air to water or from air to glass.
Light waves speed up as they move from water to air or from glass to air.
Fastest through air
Faster through water
Fastest through air
Slowest through glass

7. Refraction Glass or water air Glass or water air

8. Less dense to more dense
Give three possibilities about what Medium 1 and Medium 2 could be to make this diagram true.
First possibility
Medium 1 ________
Medium 2 ________
Second possibility
Third possibility
air
water
air
glass
water
glass

9. More dense to less dense
Give three possibilities about what Medium 1 and Medium 2 could be to make this diagram true.
First possibility
Medium 1 ________
Medium 2 ________
Second possibility
Third possibility
Give three possibilities about what Medium 1 and Medium 2 could be to make this diagram true.
First possibility
Medium 1 ________
Medium 2 ________
Second possibility
Third possibility
water
air
glass
water
glass
air

10. Convex and Concave Lenses
convergent
divergent

11. The Human Eye and Sight What type of lens is a magnifying glass?
Convergent convex
Examples of objects that use convex lenses to focus the image
Telescopes, Microscopes, Cameras,
The human eye

12. Telescope or microscope

13. Cameras
Camera uses a convex lens

14. Human eye contains two convex lenses The cornea The (secondary) lens
Light must be refracted through both lenses before it will focus on the retina.