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Flashcards in Optics Deck (27):
0

Define rarefraction

When light goes through a denser material, it bends TOWARDS the normal.

1

A concave mirror magnifies or enables a wider angle?

Magnifies eg. Dentist mirror

2

Convex mirrors magnify or enable wide angle?

Enable wide angle. Eg. Security mirror

3

A virtual image is?

Cannot be captured on screen

4

A Real image is?

Can be captured on screen

5

Define Transparent

Fully allows light to pass through (glass)

6

Non luminous

Does Not produce it's own light (moon)

7

Luminous

Produces it's own light (sun)

8

Translucent

Partially allows light to pass through (bathroom mirror)

9

Opaque

Doesn't not allow light to pass through (metal)

10

Why is a wall yellow?

When white light heats the wall, the yellow wave length is reflected, all other wave lengths being absorbed

11

To have clear sight, the image must be focused on what?

The retina

12

A thick lens has what?

A shorter focal length

13

A thin lens has what?

A longer focal length

14

For someone that is short sighted, what lens do they need?

A CONCAVE

15

For a longsighted, what lens do they need?

A CONVEX

16

What is the scattering of light?

Where the light is reflected against multiple substances, bouncing in so many directions.
This is different to the reflection of a plane mirror because wherever the light is reflected from the mirror, it bounces away from the surface in the same angle in which it came.

17

What are the two types of waves?

Transverse and compression

18

The angle of incidence is the same as?

The angle of reflection

19

Define iris

A thin circular structure in the eye

Responsible for controlling the diameter of the pupil, controlling the amount of light reaching the retina

20

Define cornea

- The cornea shields the rest of the eye from dust, germs etc.
- Controls the amount of oncoming light
- focuses 65-75%

21

Define pupil

The pupil controls the amount of light entering the eye

22

Define Lens

- Located behind the pupil
- provides fine tuning of focusing for reading the image

23

Define Optic nerve

Carries images from the retina the brain

24

Define Retina

Fine nerve tissue that transmits images to the brain

25

Light waves

- TRANSVERSE waves
- unable to travel through some substances but can travel through vacuum.
- speed in air 300 000 000m/s

26

Sound waves

-COMPRESSION waves
- travel through all liquids, solids, gases but not vacuum
- speed in air between about 330m/s and 350m/s depending on departure