Physics Higher 4 GCSE Flashcards

1
Q

What are waves

A

Vibration of atoms

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

Longitudinal waves

A

The direction of the movement of the particles is equal to the direction of the wave

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

Transverse waves

A

The direction of the movement of the particles is at 90 degrees to the direction of the wave

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

Difference between electromagnetic and mechanical waves

A

Mechanical waves need matter to travel through, but EM waves don’t

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

What is a time period of a wave

A

The time it takes for the wave to finish one wave

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

equation for wave velocity

A

wave velocity(m/s) = frequency (Hz) * wavelength (m)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How to measure the velocity of sound

A

You can time how long it takes to hear an echo of a clap when you are at a distance from a wall, you can work out the velocity of the clap too.
OR
You can connect a pair of microphones a certain distance apart to an oscilloscope.

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

What happens to sound waves when it travels across a boundary

A

When a wave travels from one medium to another, its velocity can change as well as its direction. This is called rarefaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What happens to a sound wave at a boundary

A

the sound can be:
reflected
transmitted
absorbed

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

what is ultrasound

A

sound of a frequency higher than 20,000 Hz. This means that we can’t hear it, but other animals can

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Uses of ultrasound

A

In pregnancy scans
Transmitter beams ultrasound into the mother
The waves reflect at different boundaries
The machine calculate using the time and velocity, to produce an image

Can also be used for echo-sounding and sonar

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

How does an ear work- explanation

A

As the sound travels to the eardrum, and it vibrates, it makes the ossicles vibrate. They act like levers to amplify the vibration and pass it on to the inner ear through the oval window.
The cochlea contains fluid which transmits the movements of the oval window to small hairs on the inside wall of the cochlea. These hairs are attached to sound-detecting cells that release chemical substances, which sends a signal to the brain using nerves.

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

EM spectrum

A

(increasing frequency)

Radio waves, microwaves, infrared, visible light, UV, X-Rays, gamma rays

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

What wave is an EM wave

A

a transverse wave

it has oscillating electric field and magnetic fields.

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

How are radio waves produced and detected

A

An oscillating pd across a wire makes electrons move back and forth. This produces a changing electric and magnetic field, which is emitted as a radio wave.
When the fields meet another metal, this makes the electrons move, producing an electrical signal. EM waves are also produced by the movement of electrons in atoms

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

what is the speed of an EM wave

A

It always travels at 3 * 10 to the power of 8

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is a CCD image

A

A charge-coupled device

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

How are gamma rays used for imaging

A

A doctor injects the patient with a radioactive substance that emits gamma rays.

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

Ionosphere

A

High frequency radio waves pass through the ionosphere, but lower frequency ones are reflected.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the description of a concave lens

A

Virtual, diminished, upright

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

Examples of concave lenses

A

Spy holes in doors

Back windows of coaches

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

Examples of convex lenses

A

Magnifying glass (virtual, magnified, upright)
Camera, Eye (real, diminished, inverted)
Projector (real, magnified, inverted)
Microscope (real, inverted)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

When is an image virtual

A

If it is made on the same side as the actual object

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are the 2 types of reflection

A

Specular- gives a sharp image

Diffuse- Blurry image

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Why do atoms emit radiation

A

Because they are unstable.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is alpha radiation

A

a helium atom’s nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is beta radiation

A

a fast moving electron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How can you detect radiation

A

Using a Geiger counter. A device that clicks when radiation enters it.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is alpha radiation stopped by

A

air or paper

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is beta radiation stopped by

A

Aluminium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is gamma radiation stopped by

A

Lead or concrete

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is ionising power

A

The radiation emitted by radioactive material, meaning that the radiation can remove electrons to form ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is the ionising power of all 3 radiation

A

Alpha: high
Beta: medium
Gamma: low

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Calculating with half life

A
  1. find the number of half lives in the days ( days/ half life)
  2. use that to calculate the new activity. (1/2 multiplied by itself the new activity number of times)
  3. multiply that number by the original activity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is the absorption spectrum

A

The set of frequencies of radiation absorbed by an atom when it is excited and the electron moves to a higher shell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is the emission spectrum

A

The set of frequencies of radiation emitted by an atom when the electron moves to a lower shell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Nuclear Fission

A

A larger nucleus splits into fragments and emits neutrons. It needs a neutron to start the reaction. In each splitting, more neutrons are fired out, to continue the chain reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Nuclear Fusion

A

When 2 nuclei join. It requires a lot of energy and pressure, can only be done on the Sun so far.
Releases energy through e= change in mass *speed 2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

types of stores

A
chemical
kinetic 
thermal 
gravitational 
nuclear
electrostatic 
magnetic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Thermal conductivity

A

The lower the thermal conductivity, the less heat it will conduct. So better for walls

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

how to increase efficiency

A

use insulation to reduce wasting heat
make devices from materials that reduce unwanted heat transfer
use technologies that are better at their job

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

when a ball is dropped, how does its energy store change

A

before: lots of gravity store
after: lots of kinetic store

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

when a spring is pulled, how does its energy store change

A

before: less energy in its chemical store
after: more energy in its elastic store

44
Q

when a car stops or slows down, how does its energy store change

A

before: energy in kinetic store is low
after: energy in thermal store increases

45
Q

when you lift an object, how does its energy store change

A

before: energy in kinetic and chemical store is low
after: energy in gravity store increases

46
Q

when you use a kettle, how does its energy store change

A

before: energy in chemical store is low
after: energy in thermal store increases

47
Q

average speed of someone walking

A

1 m/s

48
Q

average speed of someone running

A

5 m/s

49
Q

average speed of someone cycling

A

7 m/s

50
Q

average speed of a car

A

22 m/s

51
Q

average speed of a train

A

56 m/s

52
Q

what factors affect thinking distance

A
drinking alcohol 
drugs
tiredness
eating or drinking 
radio 
distraction by others
53
Q

equation for force

A

force= mass * acceleration

54
Q

non renewable energy sources

A

fossil fuels

nuclear fuels

55
Q

renewable energy sources

A
solar 
wind
waves 
geothermal
HEP
56
Q

what fuels are generally used for heating

A

fossil
biofuels
solar
geothermal

57
Q

what fuels are generally used for transport

A

fossil

biofuels

58
Q

what factors need to be considered when deciding on energy sources

A

cost
effect on the environment
contribution to climate change
how long the sources last

59
Q

what are the 3 wires in a plug

A

live wire- brown
neutral wire- blue
earth wire- green and yellow
earth wire: not connected t the mains, It is connected to a large metal pole buried into the ground outside your house.

60
Q

what is mains voltage

A

230 V at a frequency of 50 Hz

61
Q

What safety features are in the plugs

A

if the live wire becomes loose, it could touch the metal casing and then the casing carries a pd of 230 V. To prevent this, the earth wire connects to the earth to transport the current to the earth instead because it has less resistance than you. Also, the wire inside the fuse melts and switched off the circuit.
Or these cases can be made out of plastic, which can’t conduct electricity.

62
Q

what is red shift

A

There is an observed increase in the wavelength of the light from distant galaxies where the light is shifted towards the red end of the spectrum.

63
Q

Who came up with the red-shift theory

A

Edwin Hubble. He measured the speed of galaxies from the absorption spectrum.

64
Q

What is the Big Bang model

A

The idea that the universe started from something extremely dense and expanded suddenly 13.7 billion years ago. They believe that the universe is still expanding.

65
Q

Evidence for the Big Bang model

A

There is Cosmic Microwave Background Radiation, which was left after the Big Bang.

66
Q

4 inner rocky planets

A

Mercury, Venus, Earth and Mars

67
Q

types of orbits

A

geostationary orbit: 24 hours for one orbit and it stays fixed above the Earth’s equator. used for communications and TV.

low polar orbit: 2 hours for one orbit. Orbits over the poles for military spying and weather.

68
Q

Relationship between temperature and radiation

A

The hotter the object, the higher the frequency of radiation it will emit.

69
Q

When does the temperature of an object increase

A

if it emits less radiation than it absorbs, the temperature increases

70
Q

When does the temperature of an object decrease

A

if it emits more radiation than it absorbs

71
Q

Structure of the Earth

A

Solid inner core
Liquid outer core
Mantle can flow
Solid crust

72
Q

What are shadow zones

A

The shadow zone is the area of the earth from angular distances of 104 to 140 degrees from a given earthquake that does not receive any direct P waves. The shadow zone results from S waves being stopped entirely by the liquid core and P waves being bent (refracted) by the liquid core

73
Q

S-waves

A

Transverse- cannot travel through liquids

74
Q

P-waves

A

Longitudinal- travels through solids and liquids

75
Q

What to keep in mind when drawing a ray diagram

A

Will it bend towards or away from the normal?

76
Q

What to do if there is a circular glass block?

A

The side that meets the curved side actually shouldn’t refract at all . This is because it is travelling along the radius of the circular shape, and all radii meet the circumference at 90 degrees

77
Q

Why does the emergent light disperse into different colours?

A

White light is actually made up of many wavelengths of lights, which we see as different colours. When these different wavelengths enter the glass block, they refract by different amounts. Shorter wavelengths of light refract more than longer wavelengths. Therefore causing the colours to separate slightly. Red light has the longest wavelength and violet has the shortest wavelength, so these colours may be seen with other colours in the middle.

78
Q

how does night vision cameras work

A

they detect the objects because of its temperature difference to the surroundings

79
Q

how do x-rays generate an image of a bone

A

X-rays are absorbed by the bones in the body but transmitted by other muscles and tissues. It is shot towards a detector plate. Where there is low X-ray, it has been absorbed by bones.

80
Q

how is visible light used to transmit phone signals

A

the phone signal is converted into a series of light pulses, which are sent in an optical fibre. They repeatedly reflect off of the side of the cable till they reach the end.

81
Q

reasons for the increased risk of cancer

A

increased UV radiation. You are protected by the Earth’s atmosphere but not on other planets.

82
Q

advantages of CT scans

A

show more detail than ultrasound
give a clearer image
can be used to show both tissues and bones

83
Q

are ultrasound waves ionising?

A

no

84
Q

are x rays ionising

A

yes

85
Q

are infrared imaging ionising

A

no

86
Q

explain how infrared imaging works

A

it detects the amount of infrared radiation being given out of the body. The amount of infrared radiation increases as the temperature increases. This is then used to create an image

87
Q

advantages of gamma compared to ultrasound

A

gamma radiation can go through bones and detect tumours anywhere in the body

88
Q

disadvantages of gamma compared to ultrasound

A

gamma can cause cancer, but ultrasound can’t

89
Q

3 ways in which energy is transferred

A

radiation
conduction
convection

90
Q

Explain how adding oil reduces energy loss

A

it increases efficiency because the oil acts as a lubricant, reducing friction. Therefore, it will reduce unwanted energy transfer through heating

91
Q

what is the power rating

A

the energy transferred to an appliance per second

92
Q

How to calculate the period of a wave

A

Period = 1 / frequency

93
Q

How is heat / energy transferred?

A

Radiation
Convention
Conduction

94
Q

At what state does convection happen in

A

Gases

95
Q

At what state does conduction happen in

A

Liquids and maybe solids?

96
Q

Ways that you could make your house more energy- efficient?

A

Loft insulation reduces energy loss by convection and conduction
Hot water tank could be fitter with an insulating jacket to keep the water hot
Windows could be double glazed to prevent the loss of heat through conduction and convection.
Cavity walls could be filled with insulating foam
Central heating pipes could be covered in insulating material as well to reduce heat loss
Central heating system pipes coil die painted white to reduce the energy transferred away by heating

97
Q

What is the power rating

A

The energy transferred to an appliance per second

98
Q

What happens when you increase the height of dropping an object

A

As height increases, the gravitational potential energy increases too. This means the speed of the object being dropped increases too, therefore the kinetic energy increases.

99
Q

Why may the speed be lower than what is calculated

A

In the measurements, we ignore the effects of air resistance. So the actual speed is much lower because of air resistance that slows it down

100
Q

Explain how the red shift of light from distant galaxies provides evidence for the Big Bang model

A

Measurement of red shifts show all the galaxies are moving away from the Earth and that the more distant a galaxy is, the faster it is moving away and therefore showing a greater red shift. Something must have initially started them moving and this is likely to be the Big Bang.

101
Q

explain why some objects glow red when they are heated

A

As the temperature of an object increases, the intensity of every emitted wavelength increases. However, the intensity increases more for shorter wavelengths, than longer ones. So as objects get hotter, the peak wavelength gets shorter and moves towards the red end of the visible spectrum showing red light.

102
Q

how is temperature and intensity related

A

as the temperature increases, the intensity of each emitted wavelength in increased.

103
Q

why does the intensity increase more for shorter wavelengths

A

because shorter wavelengths of EM radiation have a higher frequency and transfer more energy. This means the peak wavelength (the most common wavelength) to decrease.

104
Q

why do hot materials cool down

A

because they emit more radiation than they absorb, eventually cooling down

105
Q

why do cold materials get hotter

A

because they absorb more radiation than they emit, eventually warming up.