2. Check & Reflect Answers p. 199
1. All mirrors obey the law of reflection. A light ray will always leave a reflective surface at the same angle it was incident. The orientation of the surface doesn’t matter.
2. Looking at the inside of the bowl is more likely to damage your eyes. The inside of the bowl is a concave surface that collects light rays to a focal point. This will make the inside of the bowl appear extremely bright. At specific angles, incident sunlight will be directed into your eyes. However, for this to occur, you have to be in a very specific position
3. The image will appear upright and larger
4. It would always appear smaller. This I because light from your face will be spread out by the mirror, appearing to come from a point behind the mirror. It doesn’t matter how far you are away from the mirror
5. Answer will vary. P. 199 gives some ideas.

3. Convex mirrors are mirrors that
A) curve inward B) curve outward C) are flat D) none of the above

4. Transparent Substances Refract Light
2.4

5. Review What happens to the image in a concave mirror when…
The object is far from the focal point?
Close to the focal point?
On the focal point?
Between the focal point and mirror?

6. Food for thought…
What happens when a truck goes off the road into deep gravel?
What happens to an army marching: ½ of them on land, ½ of them in mud?

7. Transparent Substances Refract Light
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Transparent Substances Refract Light
When a light ray strikes a boundary where two different substances meet (interface) at an angle, it will change direction.

8. Transparent Substances Refract Light
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Transparent Substances Refract Light
  Human eyes assume the light rays move through the interface in a straight line so we incorrectly identify where an object is in the other substance.

9. Example- Demo
Pie plate
Coin
water

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How Light Refracts
Refraction – bending of light as it travels from one material to another material.
-         Refraction occurs because the speed of light changes in different substances.

11. To think about… o In space (vacuum) = Light travels at 300 000 km/s
-         There are no particles in space, what happens when light strikes particles?
SLOWS DOWN : Bends towards the normal.

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As a result…
-         The denser the new medium = the more the light slows down and refracts.
 - may occur due to the number of particles in the material
Ex. Space- no particles
Air- few particles
Water- many particles
airwater diamond
= more refraction

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Therefore…
Light goes from air to water (or glass) bends towards normal
Light goes from water (or glass) to air  bends away from normal

14. Hypothesis
How will light behave it goes from air to water straight on the normal?

15. Answer
No bend from normal

16. A lens is a curved piece of transparent material (glass/plastic)
A lens is a curved piece of transparent material (glass/plastic).  When light rays pass through it, the light is refracted, causing the rays to bend. A double concave lens is thinner and flatter in the middle than the edges.  Light passing through the thicker more curved areas of the lens will bend more than light passing through the thinner areas, causing the light to spread out or diverge.
A double convex lens is thicker in the middle than around the edges.  This causes the light to come together at a focal point, or converge.

17. Homework! P. 203 1 2 3 5 Quiz Coming up after next section!!!
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Homework! P. 203 1 2 3 5
Quiz Coming up after next section!!!