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Flashcards in Light & Sound Deck (45):
1

Name the properties of light

- it is a form of energy
- it travels as a wave, electromagnetic wave
- reflects off surfaces
- speed of light 300 000 km per second

2

When light hits a surface it may be

- transmitted through it
- reflected off it
- absorbed into it

3

What is the law of reflection

Angle of incidence = angle of reflection
i = r

4

What is refraction

Refraction is the bending of light

5

Higher refraction index means

That light bends towards the normal

6

Lower refractive index

Light bends away from the normal

7

Concave lenses

A lens that curves inwards. This causes light to diverge, or spread. They spread parallel light rays as though the rays have come from a point behind he lens. Only produces images that are smaller , upright and virtual.

8

Convex lenses

A lens that is thicker at the centre. They cause light rays to come together, or converge. This is also know as a magnifying glass when held close to an object.

9

ROYGBIV

Red
Orange
Yellow
Green
Blue
Indigo
Violet

10

How can white light be turned into a rainbow

When a white light is refracted through triangular prism crystal or drop of water

11

How is sound produced

Vibration

12

How does sound travel

Longitudinal waves

13

Frequency

The numbers of waves passing a point every second

Hertz - measurement

High f = high pitch
Low f = low pitch

14

Amplitude

The force of a compression

Low a = soft sound
High a = loud sound

15

Longitudinal wave

A wave in which the vibration is in the same direction that the wave is traveling

16

Compression

A region of high pressure where particles are close together

17

Rarefaction

A region of low pressure in which particles are far apart

18

Transverse wave

A wave where the vibration is at right angles to the direction the wave is traveling

Beach wave up and down

19

Angle of incidence

An angle the incoming Ray makes with the the normal

20

Angle of reflection

The angle a reflected Ray makes with the the normal

21

Angle of refraction

The angle the refracted Ray makes with the normal

22

Diffuse reflection

Reflection of light in many directions from an uneven surface

23

Incident Ray

Incoming Ray

24

Refractive index

A measure of how easily light passes through a substance

25

Regular reflection

Reflection of light from a smooth surface such as still water or mirror. Produces clear image

26

Cornea

A transparent covering over the iris. It bends light into the lens

27

Focal length

The distance from a lens to its focus

28

Lens

In the eye it is a flexible structure the enables light to be focused on the retina

29

Long - sightedness
Hyperopia

Inability to focus on close objects because the eyeball is to long

30

Optic nerve

A nerve that carries that carries an electrical signal from the retina to the brain

31

Real image

An image formed when rays of light actually meet

32

Retina

Nerve tissue at the back of the eye. Consists of cone and rod cells, light is converted into an electrical signal here

33

Short - sightedness
Myopia

Inability to focus on long distant objects as the eyeball is to small

34

Pupil

An opening in the iris that determines the amount of light entering the eye

35

Sclera

White of the eye

36

Iris

Coloured part of the eye

37

Aqueous humour

Water fluid produced by the ciliary body to lubricate the lens and cornea

38

Vitreous humour

Clear fluid between the lens and retina

39

What is the top of the wave called

Crest

40

What is the bottom of the wave called

Trough

41

What are the primary colours

Red green blue

42

What are the secondary colours

Cyan magenta yellow

43

Ciliary body

Connected to the lens. Muscles in the body allow the shape of the lens to change

44

Chorid

Has a rich blood supply and nourishes the retina

45

Fovea

Responsible for central vision