Physics AQA P1.5 and P1.6

HideShow resource information
• Created on: 01-01-14 11:10
What is wavelength?
The distance from one wave to another
1 of 73
What is frequency?
The number of waves passing a point per second (Hz)
2 of 73
What is amplitude?
The maximum displacement of a wave between the peak and axis
3 of 73
What is the peak of a wave?
Where the hight of the wave is at a maximum
4 of 73
Describe the vibrations of a transverse wave
It has its vibrations perpendicular to the directin of energy transfer
5 of 73
What is the wavelength in a longitudinal wave?
Distance between compressions
6 of 73
What is a compression in a longitudinal wave?
Where the distance between the medium is at a minimum
7 of 73
What is a rarefaction in a longitudinal wave?
Where the distance at a medium is at a maximum
8 of 73
Describe the vibrations of a longitudinal wave
The vibrations are parallel to the direction of energy transfer
9 of 73
What type of wave is always transverse?
Electromagnetic waves
10 of 73
What are mechanical waves?
Waves that need a medium to travel through such as sound waves
11 of 73
How do you calculate wave speed?
Frequency multiplied by wavelength; v=f x λ
12 of 73
What is wave speed measured in?
Meters per second: m/s
13 of 73
What is the law of reflection?
The angle of incidence= The angle of reflection
14 of 73
What is the incident ray?
The ray that hits the mirror
15 of 73
What happens when light hits an uneven surface?
The light bounces of at different angles
16 of 73
What are the 4 rules when drawing a ray diagram?
The image is the same size as the object. The image is as far behind the mirror as the object is infront. The image is virtual and upright. The image is laterally inverted.
17 of 73
What is diffraction?
When waves bend around obstacles
18 of 73
What does diffraction depend on?
The size of the gap, when the gap is the same size as the wavelength there is maximum diffraction.
19 of 73
Why can we hear conversations in another room and not see them?
Light travels in straight lines whereas sound can diffract at a maximum around the door. This is because sound has a wavelength of 1.5m which is similar to the height of the door, 2m.
20 of 73
What is an echo an example of?
Sound reflecting off a surface
21 of 73
What will a high frequency sound wave sound like?
It will sound high pitched
22 of 73
What determines the loudness of a sound wave?
The amplitude, the larger the amplitude the louder the sound.
23 of 73
What is the range of human hearing?
20Hz - 20kHz
24 of 73
What is refraction?
When a wave enters another medium and changes its speed and direction.
25 of 73
What happens when light hits a glass block at an angle?
As it enters the block it slows down and bends towards the normal and it reflects out the block away from the normal.
26 of 73
What happens when light hits a prism?
It slows down through the prism and bends towards the normal. As it leaves it speeds up because it in a less dense medium and bends away from the normal. The light splits up into the visible spectrum; red refracted the least and violet the most.
27 of 73
List the different wave types in the electromagnetic spectrum in order
Radio waves, microwaves, infrared, visible light, ultra violet, x-rays, gamma rays
28 of 73
What happens to the wavelength as you go down the EM spectrum?
It decreases
29 of 73
What happens to the frequency and energy of the waves as you travel down the EM spectrum?
It increases
30 of 73
What is the wavelength of radio waves?
Wavelength- 1m-10^4m
31 of 73
What is the wavelength of microwaves?
Wavelength- 10^-2m
32 of 73
What is the wavelength of infrared waves?
Wavelength- 10^-5m
33 of 73
What is the wavelength of visible light waves?
Wavelength- 10^-7m
34 of 73
What is the wavelength of ultra violet waves?
Wavelength- 10^-8m
35 of 73
What is the wavelength of x-rays?
Wavelength- 10^-10m
36 of 73
What is the wavelength of gamma rays?
Wavelength- 10^-15m
37 of 73
What are radio waves used for?
38 of 73
How is long wave radio transmitted over the world?
The wavelengths are longer (1-10 km) so they can diffract over the curved surface of the Earth
39 of 73
The are reflected off the ionosphere
40 of 73
The wavelength is very short (10cm-10m) so the receiver must be in direct line of the transmitter for the transmissions to be received
41 of 73
What are radio waves created by?
Manmade transmitters and natural sourced such as lightning
42 of 73
What are microwaves used for?
Satellite communication, mobile phones, cooking
43 of 73
Why are microwaves used for satellite communication?
Because microwaves can pass easily through the Earth's early atmosphere
44 of 73
How does satellite TV work?
The signal from a transmitter is sent into space and picked up by a satellite receiver dish. The signal is transmitted back to Earth in another direction, where it is received by a satellite dish on ground.
45 of 73
What are microwaves created by?
46 of 73
What are the dangers of microwaves?
Thermal damage
47 of 73
What are infrared waves used for?
Remotes and in optical fibre
48 of 73
How do remote controls use infrared radiation?
Different patterns of infrared waves, sending different commands
49 of 73
How do optical fibres work?
The signal is carried as pulses of light or infrared radiation and is reflected off the sides of a narrow core from one end of the fibre to the other
50 of 73
What are the benefits of optical fibre use instead of radio waves or microwaves?
They are more secure since signals are reflected back in and they carry more information since the wavelengths are shorter
51 of 73
What is visible light used for?
Seeing, photography
52 of 73
What are the dangers of visible light?
Intense light can damage eyes, cause chemical reactions and cancer
53 of 73
What are ultraviolet waves used for?
Forgery detection, forensics and killing bacteria
54 of 73
What are ultraviolet waves created by?
Stars, sun beds and blacklights
55 of 73
What are the dangers of ultraviolet waves?
Skin cancer, burns and ageing
56 of 73
What are x-rays used for?
57 of 73
What are the dangers of x-rays?
58 of 73
What are gamma waves used for?
Killing cells (cancer treatment) and sterilisation
59 of 73
What are gamma waves created by?
60 of 73
What are gamma waves detected by?
A geiger counter
61 of 73
What are dangers of gamma waves?
Serious skin damage
62 of 73
What is the doppler effect?
When a wave source moving towards or away from you the wavelengths and frequency seem different to when the wave source is stationary
63 of 73
What happens to the sound waves of a stationary object?
They are equally spaced
64 of 73
What happens to the sound waves of an object moving towards you?
The frequency seems higher and the wavelength seems shorter, it has a higher pitch
65 of 73
What happens to the sound waves of an object moving away from you?
The frequency seems lower and its wavelength seems longer, it has a lower pitch
66 of 73
Which types of waves does the doppler effect apply for?
Both longitudinal and transverse waves
67 of 73
What is red-shift?
The wavelength of light of distant galaxies is nearer the red end of the visible light spectrum, because their light it stretched so their wavelength appears longer.
68 of 73
What does red-shift suggest?
Galaxies are moving away from us
69 of 73
The further away the galaxy...
The more red shifted it is, this suggests the universe is expanding
70 of 73
What does the Big Bang theory state?
The universe is expanding after it exploded from one compressed point
71 of 73
What is the Steady State theory?
The Earth has always existed as it is now and that galaxies are being pushed apart by matter entering the universe through white holes
72 of 73
What is cosmic microwave background radiation?
This is the radiation detected all over the universe. It can only be explained by the Big Bang. Just after the explosion high frequency radiation was produced which spread out and progressed to microwave radiation as the Earth cooled.
73 of 73

Other cards in this set

Card 2

Front

What is frequency?

Back

The number of waves passing a point per second (Hz)

Card 3

Front

What is amplitude?

Card 4

Front

What is the peak of a wave?

Card 5

Front

Describe the vibrations of a transverse wave