cycle test 3 yr9

Question 1

example of a longitudinal wave

Answer 1

sound

Question 2

example of a transverse wave

Answer 2

light

Question 3

what are the two main parts/features of a longitudinal wave

Answer 3

compressions and rarefactions

Question 4

what are the two main parts/features of a transverse wave

Answer 4

troughs and crests

Question 5

do longitudinal waves require a medium

Answer 5

yes, for vibrations to occur

Question 6

do transverse waves require a medium

Answer 6

not required, can travel through vacumes

Question 7

how is the energy transferred in a longitudinal wave?

Answer 7

the energy is transferred through vibrations in the direction of the wave (side to side)

Question 8

how is the energy transferred in a transverse wave?

Answer 8

The energy is transferred vertically to the direction of the wave

Question 9

amplitude in sound affects:

Answer 9

the volume

Question 10

frequency in sound affects:

Answer 10

pitch

Question 11

what is a period

Answer 11

The time it takes for two successive crests (one wavelength) to pass a point, or one full wave sycle

Question 12

what is a wavelength

Answer 12

the distance between two identical points in a wave (eg. trough to trough)

Question 13

what is an oscilloscope?

Answer 13

a device used to watch/study changing signals eg. sound waves and currents

Question 14

what is period shown as and measured in

Answer 14

t, or time, measured in seconds

Question 15

what is frequency

Answer 15

how many full cycles per second

Question 16

what is frequency measured in

Answer 16

hertz (1 cycle = 1 hertz)

Question 17

what is amplitude

Answer 17

the baseline (graph) to the crest of a wave

Question 18

how to calculate frequency

Answer 18

1/period of time

Question 19

how to calculate period

Answer 19

1/frequency

Question 20

what is wave speed measured in

Answer 20

m/s

Question 21

velocity is shown as

Answer 21

v

Question 22

velocity is calculated by

Answer 22

frequency times wavelenth

Question 23

if you decrease wavelength you

Answer 23

increase frequency

Question 24

does increasing the frequency alter the wave speed?

Answer 24

no! instead the wavelength will decrease proportionally (inversely)

Question 25

speed equals

Answer 25

distance over time

Question 26

what is the speed of light

Answer 26

3 times 10 to the power of 8 m/s

Question 27

is ultrasound higher or lower than a humans range of hearing?

Answer 27

higher

Question 28

is infrasound higher or lower than a humans range of hearing?

Answer 28

lower

Question 29

what is the range of human hearing

Answer 29

20-20000

Question 30

what are some qualities of ultrasound waves

Answer 30

high f, low wavelength, converts electrical energy to sound for use in imaging

Question 31

what kind of waves are x-rays

Answer 31

light waves, electro magnetic

Question 31

why is it important to have high frequency and low wavelengths in ultrasound imaging

Answer 31

less diffraction, and therefore clearer images

Question 32

what are some differences between ultrasound and x-rays (don't look) ultrasound reflects of tissues to produce images, can show soft tissue and fluid sensors detect the reflection produces a real time vid safe, non ionising waves

Answer 32

x-rays is blocked by pones (prevents light from affecting filter screen) so used for looking at bones film detects light coming through (or lack of (white parts)) image is developed after ionising radiation is created

Question 33

how does an oscilloscope measure waves

Answer 33

it converts sound waves into electric signals that can be viewed on a screen

Question 34

what spectrum are light waves on?

Answer 34

Electro-magnetic spectrum

Question 35

what are some qualities of radio waves

Answer 35

low energy and danger

Question 36

what are radio waves used for

Answer 36

communication (not as sound waves)

Question 37

how large do radio waves have to be to be reflected by the ionosphere

Answer 37

10m (any smaller and they pass through)

Question 38

How do microwaves interact with water and metals

Answer 38

they are absorbed by water and reflected by metals

Question 39

how do microwaves interact with glass, paper and plastic?

Answer 39

they pass through

Question 40

What is infrared emitted by

Answer 40

objects emitting heat energy/ reflecting it

Question 41

what is ultraviolet light emitted by

Answer 41

the sun and other white hot objects

Question 42

how does ultraviolet light interact with the environment?

Answer 42

it is absorbed by solids and passes through air

Question 43

how does ultraviolet light affect humans

Answer 43

it increases melanin production, and can causes burns and cancer if overexposed

Question 44

what are some properties of gamma radiation

Answer 44

extremely high frequency and short wavelengths, most penetrating and ionising radiation

Question 45

what is gamma radiation emitted by?

Answer 45

radioactive substances

Question 46

definition of refraction

Answer 46

change of a direction of light (causes dispersion and bending of light)

Question 47

what is the iris?

Answer 47

the coloured part of the eye that controls the dilation and contraction of the pupil

Question 48

what is the pupil

Answer 48

hole in the center of the eye where light passes through to reach the retina

Question 49

what is the law of relfection

Answer 49

angle of incidence and reflection are equal

Question 50

what are the two kinds of reflection

Answer 50

specular and diffuse

Question 51

what does the lens do

Answer 51

it refracts light towards the retina

Question 52

what is the retina

Answer 52

receptor cells that detect light and sends impulses to the brain via the optic nerve.

Question 53

what is diffuse reflection

Answer 53

scattered reflections that produce an unclear image

Question 54

specular reflection

Answer 54

clear and even image (produced with a mirror like/smooth material)

Question 55

what is refraction

Answer 55

when a wave or light ray moves from one medium to another, causes a change in direction of light (due to speed changes)

Question 56

what is the critical angle

Answer 56

an angle that defines the minimum point of total internal reflection

Question 57

If the medium of refraction is less dense what happens to the light ray

Answer 57

it bends towards the normal

Question 58

If the medium of refraction is more dense what happens to the light ray

Answer 58

the light ray bends away from the normal

Question 59

the lower the amplitude:

Answer 59

the quieter the volume

Question 60

the lower the frequency:

Answer 60

the lower the pitch