Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

GCSE Physics > P2 - Waves > Flashcards

P2 - Waves Flashcards

You may prefer our related Brainscape-certified flashcards:
GCSE Geography - AQA flashcards Physics 101 flashcards GCSE Religious Studies - Edexcel Route B flashcards GCSE Religious Studies - Eduqas Route A flashcards GCSE Religious Studies - Edexcel Route A flashcards GCSE Religious Studies - Eduqas Route B flashcards AP® Physics flashcards
1
Q

Describe the differences between transverse and longitudinal waves

A
  • Transverse waves (eg water waves) oscillations are perpendicular to direction of energy transfer
  • Longitudinal waves (eg sound) oscillations are parallel to energy transfers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is frequency?

A

number of waves passing a fixed point per second, measured in Hertz (Hz)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is amplitude?

A

maximum displacement of any particles for undisturbed position (m)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is wavelength?

A

the distance from one point on a wave to the equivalent point on the next wave (m)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is a wave period?

A

time taken for one complete oscillation (s)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What happens when waves pass between different mediums?

A
  • wavelength changes
  • frequency doesn’t change because same amount of waves are still being produced per second
  • speed and wavelength are directly proportional
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What happens when waves reach boundary between two medium?

A

reflected, refracted, absorbed, transmitted

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the refractive index?

A

The way in which a material affects refraction

  • low to high RI bends towards normal
  • high to low RI bends away from normal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Why does refraction happen?

A

difference of wave speed in different mediums

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What happens when a light wave enters a medium, at an angle, where it travels slower?

A
  • first part of wave slows down
  • rest of wave continues at high speed
  • changes direction towards normal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the range of human hearing?

A

20 Hz to 20kHz (20 000Hz) - frequencies at which the ear drum can vibrate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Why can’t ultrasound waves be heard by humans?

A

frequency higher than 20kHz

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What happens when an ultrasonic wave meets a boundary between two mediums? How can this be used?

A
  • partially reflected

- helps find how far away a boundary is, measure time taken for ultrasonic wave to return to detector

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How are ultrasound waves used in industry?

A
  • defects in materials (cracks, air bubbles, corrosion)

- medicine (pre-natal scans, kidney stones, tumours, images of damaged ligaments or muscles)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is echo sounding?

A

use of ultrasonic waves for detecting objects in deep water and measuring water depth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How does echo sounding work?

A
  • ultrasonic pulse see in to water, reflected back when it hits a surface
  • time between pulse being send and reflected detected can be used to calculate distance (remember to /2 as it is in both directions)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the speed of sound in water?

A

1500m/s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the 2 types of seismic waves?

A

p-waves (primary)

s-waves (secondary)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Describe P-waves

A
  • longitudinal
  • speed of sound
  • twice as fast as s-waves
  • different speeds through liquids and solids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Describe s-waves

A
  • transverse

- can’t travel through liquids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How can seismic waves be used to locate earthquakes and different materials they have travelled through?

A

difference in time of arrival of P and S waves at different detectors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

In terms of seismic waves, what happens during an earthquake?

A
  • seismic waves travel outwards from earthquake and can travel all the way through earth
  • seismic waves travel in a curved path due to earth increasing in density with depth
  • detectors placed around the earth measure when and where different waves around
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What evidence is given by the s-wave shadow zone?

A
  • s waves can’t travel through liquid outer core
  • large shadow zone on opposite side of earth where earthquake originates
  • this shadow zone shows size of earth’s core
24
Q

What evidence is given by the p-wave shadow zone?

A
  • able to travel through liquid outer core
  • refracted at boundary between semi solid mantle and liquid outer core
  • refract again and boundary between liquid outer core and solid inner core
  • refractions = shadow zones
  • determines size and composition of inner and outer core
25
Q

Describe EM waves

A
  • transverse
  • same velocity in air or vacuum (speed of light)
  • wavelength affects how it is absorbed, transmitted, reflected or refracted, changing its uses
26
Q

Recall the order of the electromagnetic spectrum from low frequency, long wavelength to high frequency, short wavelength

A 
radio waves
microwaves
infrared
visible light
ultraviolet
x rays
gamma
27
Q

What are the uses of radio waves and why?

A
  • tv, radio, bluetooth

- low energy so not harmful

28
Q

What are the uses of microwaves and why?

A
  • satellite, cooking

- travel in straight lines, ideal for transmitting donald to satellites in orbit and back down to receivers

29
Q

What are the uses of infrared and why?

A
  • heaters, cooking, camera

- glow red as electricity flows, transmits infrared energy absorbed by food and converted back into heat

30
Q

What are the uses of visible light waves and why?

A
  • fibre optics

- visible light travels down optical fibres from one end to the other without being lost through the sides

31
Q

What are the uses of UV light waves and why?

A

energy efficient life bulbs (UV produced by gas in bulb, absorbs by coating on bulb which fluoresces)
security marking, sun beds

32
Q

What are the uses of x-rays waves and why?

A

-medical imaging and treatment

can penetrate soft tissue and bone, showing shadows where bones are

33
Q

What are the uses of gamma ray waves and why?

A

sterilising food, treating tumours

most energetic of all waves so can destroy bacteria and tumours

34
Q

What are radio waves caused by?

A

oscillations in electrical circuits (alternating current)

35
Q

What does frequency of radio wave depend on?

A

frequency of electrical oscillation

36
Q

How is a radio signal received?

A

Radio waves absorbed by a conductor with same frequency as the wave

37
Q

How can changes in atoms or nuclei generate or absorb EM waves?

A
  • electrons moving between energy levels due to heat or electrical energy
  • nucleus of an atom generates wave (unstable nucleus emits excess gamma rays)
38
Q

What EM waves are harmful enough to damage the human body? How?

A
  • UV can cause skin to age prematurely and increase risk of skin cancer
  • X and gamma are ionising radiation: cells that absorb them can have no change, mutate (leading to cancer) and die (burns, sickness, death)
39
Q

What is a real image?

A

opposite side of lens to objects and can be projected on to screen

40
Q

What is a virtual image?

A

same side as the object, can only be seen through the lens

41
Q

Describe the difference between concave and convex lenses

A

Convex

  • wider in middle
  • rays converge

Concave

  • wider at edges than middle
  • diverging rays
  • rays appear to have come from same principal focus on same side of lens as the originated (track diverging rays back behind lens)
42
Q

What is visible light?

A

em waves detectable by human eye

43
Q

What is reflection from a smooth surface in a single direction called?

A

speculate reflection

44
Q

What is scattered reflection from a rough surface called?

A

diffuse reflection

45
Q

Define:
transparent
translucent
opaque

A

transparent - transmits light coherently
translucent - transmit light but scattered rays
opaque - reflect or absorb all light so no light passes through

46
Q

Why do objects appear a certain colour?

A
  • reflects light of that particular wavelength

- absorbing all other wavelength

47
Q

Why do objects appear white?

A

reflecting all rays equally

48
Q

Why do objects appear black?

A

All wavelengths absorbed

49
Q

How do colour filters work?

A
  • absorb some wavelengths and not others
  • transmitted wavelengths control what colour the filter allows the pass through
    they do not mix colours, just absorb and transmit
50
Q

When a filter is the same colour as the object, what happens?

A

the object will appear it’s true colour

51
Q

What will happen if an object is a different colour to the filter?

A
  • the object will appear black
52
Q

All bodies ___________ and ___________ infrared radiation

A

emit, absorb

53
Q

What effect does increasing temperature have on infrared emission?

A
  • The hotter the body, the fast it emits infrared radiation
  • intensify if shorter wavelengths increase faster
  • goes from red to white
54
Q

Define a perfect black body

A
  • absorbs all infrared incident on it
  • does not reflect or transmit any
  • good absorber = good emitter, so perfect black bodies are best possible emitters as well as absorbers
55
Q

What does the temperature of a body depend on?

A
  • rate of emitting radiation

- wavelength of radiation it emits

56
Q

Explain how the term pasture if the Earth is determined by emitted and absorbed radiation

A
  • ground on a sunny day increases in temperature
  • because it absorbs radiation fast than it emits
  • warmer the ground gets the faster it emits radiation
  • constant temperature: emission = absorb
57
Q

What does the temperature of the earth depend on?

A
  • how much energy received from sun
  • how much energy is reflected back in to space
  • how much energy emitted in to space

GCSE Physics (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions