Brainscape's Knowledge GenomeTM

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


See full index

Science A (Core): Physics (I) > Science A (Core): Physics > Flashcards

Science A (Core): Physics Flashcards

You may prefer our related Brainscape-certified flashcards:
Physics 101 flashcards AP® Physics flashcards Biology 101 flashcards
1
Q

What are the 3 ways in which energy can travel?

A

Conduction, convection and radiation

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

Explain what conduction is

A

When energy is passed from one particle to another (via vibrations)

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

What type of materials are good conductors and what type of materials are bad conductors (good insulators)?

A

Metals are good conductors (e.g. copper) and non-metals are good insulators (e.g. plastics)

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

Does conduction happen best in solids, liquids or gases?

Explain your answer

A

Solids – the particles are close together

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

Explain what convection is

A

Heat rises because particles gain energy, spreading out and becoming less dense – when they lose energy they become more dense, sinking and forming the convection current

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

What is a vacuum and which forms of energy movement does it stop (convection / conduction / radiation)

A

A vacuum is a space with no particles – this prevents energy transfer via conduction and convection (radiation can pass)

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

Does convection happen best in solids, liquids or gases?

Explain your answer

A

Convection happens best in liquids and gases as the particles are able to move

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

How does the outside temperature affect the rate at which heat is transferred?

A

The greater the temperature difference the greater the heat transfer (loss or gain)

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

What type of objects usually emits radiation energy?

A

Hot objects as well as black objects are good emitters of radiation

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

What type of material absorbs radiation and what type of material reflects radiation?

A

Black matt materials absorb radiation the most

White shiny materials reflect radiation the most

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

Which home insulation methods are usually the most cost effective?

A

Cavity wall insulation

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

Give 3 examples of how energy can be lost from a house and explain how heat loss can be reduced

A

Windows – use double glazing / thick curtains

Walls – use cavity wall insulation

Loft – use loft insulation (fibre glass)

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

What are the 10 types of energy? Explain each one

A

Electrical; light; sound; kinetic (movement); nuclear; thermal (heat transfer from hot to cold objects); radiant (electromagnetic radiation from hot objects); gravitational potential; elastic potential; and chemical

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

What 2 things affect the amount of energy an appliance transfers?

A

Power and length of time the appliance is on

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

What is power, and what units is it measured in?

A

Power means “how much energy per second”, measured in watts (W) or kilowatts (kW)

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

What is the equation for working out power?

A

Power (W) = Energy (J) ÷ Time (s)

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

What units is energy measured with?

A

Joules (J) or kilojoules (kJ)

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

Draw out the following energy transfers: -

Toaster

Battery operated torch

Skateboarding down a hill

Solar operated fan

A

Toaster – electrical → thermal

Battery operated torch – chemical → electrical → light (+ thermal)

Skateboarding – gravitational potential → kinetic → thermal (frictional)

Solar operated fan – light → electrical → kinetic

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

What happens to the energy that is wasted in energy transfers?

A

It is transferred to the surroundings (usually heating the surroundings up)

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

What does energy efficiency mean and how is it worked out?

A

Efficient devices transfer more energy (wasting less)

Efficiency = useful energy output ÷ total energy inpu

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

How would you make these items more efficient: -

Toaster

Light bulb

Car

A

Toaster – stop it losing light

Light bulb – stop it losing heat

Car – stop it losing heat and sound

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

What are the different energy resources?

A

Solar; tidal; wind; geothermal; hydroelectric; fossil fuels; nuclear; wave

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

What are the 3 types of fossil fuel?

A

Coal, oil and natural gas

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

How can you work out the cost of energy transferred from the mains supply?

A

Energy transfer = kilowatt hours x cost per unit

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

What is the difference between renewable and non-renewable energy resources? Give examples of each

A

Renewable resources can never run out (e.g. wind) whilst non-renewable resources will

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

Explain how fossil fuel or nuclear power stations work

A

Fuel is burnt / reacted producing heat, turning water to steam – the steam turns a turbine which turns a generator, producing electricity

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

What is the job of a turbine?

A

Turbines are designed to spin a generator

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

How do generators work (what are they made of)?

A

Generators have a magnet, which spins within a coil of wire, inducing an electrical charge

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

Why are fossil fuels bad for the environment?

A

Fossil fuels release carbon dioxide (CO2), which can lead to global warming (+ sulfur dioxide which leads to acid rain)

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

What causes acid rain, and why is it an environmental problem?

A

Sulfur dioxide causes acid rain (which can kill plants and fish etc…)

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

What causes global warming, and why is this bad for the environment?

A

Carbon dioxide causes global warming (increases temperature which can cause ice caps to melt resulting in flooding etc…)

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

How does the national grid utilise step-up and step-down transformers?

A

Step-up transformers increase the voltage before the electricity goes into the cables – meaning the electricity is carried more efficiently (as there is less heat loss)

Step-down transformers reduce the voltage before the electricity reaches our house (making it safer)

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

What happens to the current when the voltage is increased – how does this affect heat loss from electrical cables?

A

Step-up transformer increases the voltage decreases the current (reducing heat loss from the cables)

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

What are the pros and cons of producing energy using nuclear fuel?

A

Pros – no carbon dioxide or sulfur dioxide so no global warming / acid rain; is reliable

Cons – toxic waste and expensive to decommission

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What are the pros and cons of producing energy using wind turbines?

A

Pros – no carbon dioxide or sulfur dioxide so no global warming / acid rain; is renewable and reliable

Cons – ugly and noisy; unreliable; take up a lot of space

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

How can geothermal energy be used to generate electricity? What are the pros and cons?

A

Pipes take water down to hot rocks within the Earth (water is heated, forming steam which turns turbines which spin generators)

Pros – no carbon dioxide or sulfur dioxide so no global warming / acid rain; is renewable and reliable

Cons – few areas suitable

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

How can tidal energy be used to generate electricity? What are the pros and cons?

A

Tides run through turbines (on tidal barrages), which spin generators

Pros – no carbon dioxide or sulfur dioxide so no global warming / acid rain and is renewable

Cons – affects habitats of wading birds and is unreliable

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

How can hydroelectric energy be used to generate electricity? What are the pros and cons?

A

Water falls through turbines, which spin generators

Pros – no carbon dioxide or sulfur dioxide so no global warming / acid rain; is renewable; reliable and can be stored

Cons – environmentally damaging to area (destroys habitat / ecosystems)

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

Order the following which generate electricity fastest: coal; oil; gas; and nuclear

A

Gas

Oil

Coal

Nuclear

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

How can the Sun be used to generate electricity? What are the pros and cons?

A

Solar cells use light energy to generate electrical current

Pros – no carbon dioxide or sulfur dioxide so no global warming / acid rain; is renewable

Cons – very expensive and is unreliable

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

What is the main advantage of using non-renewable resources rather than renewable resources?

A

Non-renewable energy resources release a lot of energy quickly, and relatively cheaply

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

How are the particles in a solid arranged?

What movement can occur?

A

Close together with a regular pattern

Particles are able to vibrate on the spot

43
Q

How are the particles in a gas arranged?

What movement can occur?

A

Far apart and random

Particles are able to move quickly in all directions

44
Q

How are the particles in a liquid arranged?

What movement can occur?

A

Close together but random

Particles are able to move around one another

45
Q

Draw out a basic heating curve for water (melting point 0oC and boiling point 100oC)

A
46
Q

Draw out a basic cooling curve for salol (melting point 69oC)

A
47
Q

Where are metals generally extremely good at conducting both heat and electricity?

A

Metals have a sea of delocalised electrons – these gain energy when the metal is heated and as they are not attached to any specific atom can move through the metal quickly

48
Q

What is a Leslie cube?

A

A Leslie cube is a device which has sides made of different materials – when filled with hot water the energy emitted from each surface will vary

49
Q

How does a thermos flask work to reduce heat loss (by design)?

A

A thermos flask reduces heat loss via conduction, convection and radiation

50
Q

Explain the key principles of a thermos flask and how it works

A

Glass bottle is double-walled with a vacuum between the two walls

Walls either side of the vacuum are silvered

Bottle is supported by insulating form

Stopper is made of plastic and filled with cork or foam

The whole design minimises any heat loss through conduction, convection or radiation

51
Q

How does evaporation help when we sweat?

A

Evaporation helps to cool us down by removing heat from our body to the environment (utilising sweat) – as the sweat evaporates from liquid to gas a small amount of heat is taken from that area of the skin…

52
Q

Why does condensation occur?

A

When particles lose enough energy to the surroundings they can change state from a gas to a liquid

53
Q

How do plants keep themselves cool?

A

Plants utilise a transpiration stream to keep themselves cool – water is moved from the roots to the surface of the leaves where it evaporates

54
Q

What is a U-Value?

What does it measure?

A

A U-Value is a measurement of the effectiveness of the insulation in a home – the lower the U-Value the more effective the insulation

55
Q

What is payback time?

A

Payback time is the time it takes to get your money back from investing in insulation

Payback time (years) = cost of insulation (£) ÷ savings per year in fuel costs (£)

56
Q

What is specific heat capacity and how can it be worked out?

A

The amount of energy it takes to heat up 1kg of the substance by 1oC – this is the specific heat capacity

57
Q

What is the equation to work out the energy needed to heat something?

A

Energy (J) = Mass (kg) x Specific Heat Capacity (c) x Change in Temperature (oC)

Q = mc∆T

58
Q

What is a Sankey diagram?

A

Sankey diagrams summarise the energy transfers occurring

59
Q

What are efficiency ratings?

A

Efficiency ratings show how much energy an appliance (or house) uses as well as an indication to their running costs

60
Q

What is a power rating?

A

Power rating is how much energy a device uses (1 watt = 1 joule per second)

61
Q

What are generators and how do they work?

A

Generators are devices which transfer kinetic energy into electrical – they induce a current by spinning a coil of wire within a magnet (or magnet within a coil of wire)

62
Q

How are generators spun?

A

Generators are spun via a connecting turbine – this is either spun directly (i.e. from a wind farm) or turned when fossils fuels or nuclear fuel heats water which turns to steam and drives the turbine

63
Q

What do waves transfer?

(They do this without transferring what?)

A

Transfer energy without transferring matter

64
Q

Draw and label this wave: -

A

Frequency – number of waves produced each second (Hz)

65
Q

What do all electromagnetic waves have in common?

A

They all travel at the same speed through a vacuum – the speed of light (300’000’000m/s)

66
Q

Name the electromagnetic spectrum from shortest to longest wavelength

A

Gamma (shortest)

X-rays

Ultra-violet

Visible light

Infra red

Microwaves

Radio waves (longest)

67
Q

What is a longitudinal wave and what does it look like?

A

Vibrations in the same direction as the wave (e.g. sound)

68
Q

What can happen when radiation is absorbed by a substance?

A

Radiation may make things hotter, or set up an alternating current with the same frequency as the radiation itself

69
Q

What are the effects of these types of electromagnetic radiation on living cells: -

Radio waves & visible light

Microwaves & infrared

X-rays, UV and gamma rays

A

Radio waves & visible light have very little effect on cells

Microwaves and infrared can cause heating of cells

X-rays, UV and gamma rays can cause ionization of cells and lead to mutations, cancers and death

70
Q

How can the harmful effects of X-rays be reduced?

A

Reducing exposure & using lead aprons

71
Q

How can the harmful effects of UV radiation be reduced?

A

Reduce exposure to the Sun (using a broad spectrum sun screen)

72
Q

How are these electromagnetic waves used: -

Radio waves

Microwaves

A

Radio waves: communications

Microwaves: heating food & sending information (e.g. mobile phones)

73
Q

How are these electromagnetic waves used: -

Infrared

Visible light

A

Infrared: communications (phone & via optical fibres), remote controls and electric heaters

Visible light: used to send information via optical fibres

74
Q

How are these electromagnetic waves used: -

Ultra-violet

X-rays

A

UV: security tags and sun-beds

X-rays: imaging the body (broken bones)

75
Q

How are gamma rays used?

A

Sterilising surgical equipment by killing bacteria & radiotherapy for cancer patients

76
Q

Which 4 forms of electromagnetic radiation can be used for communications?

A

Communications via: radio waves, microwaves, infrared waves (optical fibres) and visible light (optical fibres)

77
Q

Why are microwaves used to communicate with satellites?

A

Microwaves are able to pass through the Earth’s atmosphere to reach the distant satellites

78
Q

What is a transverse wave and what does it look like?

A

Vibrations which are sideways (e.g. light)

79
Q

What are rarefactions and compressions?

A

Regions where the wave is pulled apart (rarefactions) and pushed together (compressions)

80
Q

What is the formula for calculating the speed of a wave (triangle will also help)

A

Speed (m/s) = Frequency (Hz) x Wavelength (m)

81
Q

What properties effect waves?

A

Waves can be reflected, refracted and diffracted

82
Q

How can light be reflected?

A

Light can reflect off an even surface (clear) or from an uneven surface (diffuse)

83
Q

What is refraction?

A

Refraction occurs as light can bend at the boundary between materials of different densities

84
Q

Draw out an angle of incidence and an angle of reflection

A

Angle of incidence = angle of reflection

85
Q

How can the refractive index be worked out?

A

Refractive index = sin i ÷ sin r

86
Q

What is constructive interference?

A

Where two waves arrive in step reinforcing one another (increasing the amplitude)

87
Q

What happens if the size of a gap is made similar to the wavelength of a wave?

A

Diffraction increases

88
Q

What is destructive interference?

A

Where two waves arrive out of step cancelling one another out

89
Q

What happens to diffraction if the wavelength is increased?

A

Diffraction increases

90
Q

What does this picture show?

A

Reflection

91
Q

What does this picture show?

A

Refraction

92
Q

What does this picture show?

A

Refraction

93
Q

What does this picture show?

A

Diffraction

94
Q

What does the red-shift provide evidence for?

A

The big bang – galaxies are moving away from us, providing evidence that the universe is still expanding after the explosion of the big bang

95
Q

How do optic fibres work, and what are they used for?

A

Optic fibres carry information (light / infra red) via total internal reflection (used for networking / endoscopes)

96
Q

How do people who work with radiation monitor their exposure?

A

Photo film badges, half covered with paper and half covered with foil – the film turns black if radiation hits it (top half = beta, all = gamma)

97
Q

What is red-shift?

A

When light rays moving away from us appear red, as the wavelength becomes stretched

98
Q

What is cosmic microwave background radiation?

A

The relatively uniform background radiation is the remains of energy created just after the Big Bang

99
Q

What is amplitude?

A

A measure of how loud a sound is (how much energy is carried)

100
Q

What is pitch?

A

Pitch is how high or low a sound is, dependent upon the frequency of the waves

101
Q

What properties does an image in a plane mirror have?

A

Image is the same size, it is as far behind the mirror as the object is in front, and it is formed from diverging rays meaning it is virtual

102
Q

Draw an image as shown in a plane mirror

A

Plane mirror image

103
Q

What type of EM radiation can we detect?

A

Visible light

104
Q

What colour of light is refracted the most and why?

A

Violet (it has the shortest wavelength)

Science A (Core): Physics (I) (1 decks)

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