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Flashcards in Year 9 Physics Deck (41):
1

Define Wave...

A wave is a transmitter of energy without the movement of particles from place to place. The vibration of particles or energy fields is involved.

2

Define Transverse Waves...

wave involving the vibration of particles perpendicular to the direction of energy transfer

3

Define Compression Waves ...

wave involving the vibration of particles in the same direction as energy transfer

4

What is Longitudinal wave?

Another word for compression wave.

5

Define a Medium...

material through which a wave moves

6

Vibration

repeated fast back-and-forth movements

7

Define Compression ...

region in which the particles are closer than when not disturbed by a wave

8

Define Rarefaction...

region in which the particles are further apart than when not disturbed by a wave

9

Define Frequency...

number of vibrations in one second, or the number of wavelengths passing in one second

10

Define Pitch...

highness or lowness of a sound. The pitch that you hear depends on the frequency of the vibrating air.

11

Define Hertz...

unit of frequency; its abbreviation is Hz. One hertz is equal to one vibration every second.

12

Define Wavelength...

distance between two neighbouring crests or troughs of a wave. This is the distance between two particles vibrating in step.

13

Define Amplitude...

maximum distance that a particle moves away from its undisturbed position

14

Define Sonar ( SOund Navigation and Ranging )...

use of reflected sound waves to locate objects under water (sound navigation and ranging)( SOund Navigation and Ranging )

15

Define Echolocation...

use of sound to locate objects by detecting echoes

16

Define Ultrasound

sound with frequencies too high for humans to hear

17

Ear Canal

the tube that leads from the outside of the ear to the eardrum

18

Eardrum

a thin piece of stretched skin inside the ear that vibrates when sound waves reach it

19

Membrane

Thin layer of tissue

20

Auricle

the fleshy outside part of the ear

21

Cochlea

the snail-shaped part of the inner ear. It is lined with tiny hairs that are vibrated by sound and stimulate the hearing receptors.

22

Semicircular canal

three curved tubes, filled with fluid, in the inner ear that control your sense of balance

23

Auditory Nerve

a large nerve that sends signals to the brain from the hearing receptors in the cochlea

24

Ossicles

a set of three tiny bones that send vibrations from the eardrum to the inner ear. They also make the vibrations larger.

25

Oval window

an egg-shaped hole covered with a thin tissue. It is the entrance from the middle ear to the outer ear.

26

Relative intensity

A measure of how loud a sound is using a sound meter

27

Sound level

the energy of sound that is an indication of the loudness of a sound

28

Decibel

(dB) unit of measurement of relative sound intensity

29

Threshold hearing

the lowest level of sound that can be heard by the human ear

30

Threshold of pain

the lowest level of sound that causes pain to the human ear

31

Tinnitus

ringing or similar sensation of sound in the ears, caused by damage to the cells of the inner ear

32

Cochlear implant

a device implanted behind the ear that detects and processes sound, then sends signals to the auditory nerve so that severely deaf people can hear

33

Bionic ear

cochlear implant

34

Rays

narrow beams of light, You cannot see a single light ray.

35

Beam

wide stream of light rays, all moving in the same direction, You can see beams of light only when particles in substances like air scatter,

36

Reflection

bouncing off the surface of a substance

37

Luminous

releasing its own light

38

Scattering

describes light sent in many directions by small particles within a substance

39

Transparent

describes a substance that allows most light to pass through it. Objects can be seen clearly through transparent substances.

40

Translucent

allowing light to come through imperfectly, as in frosted glass

41

Opaque

describes a substance that does not allow any light to pass through it