Learning Objective: Recap all of the
physics content with past paper
questions
Topic
Kinetic particle theory
Transfer of energy
Heat and the home
Energy efficiency
Generating electricity
Cost of electricity
Waves
Origins of the Universe
Slide numbers
3-18
19-35
36-45
46-67
68-79
80-89
90-120
121-135
 Good-
know the key facts in the physics
module
 EBI-
You can apply what we recap to past
paper questions
 Excellent-
question
You can get 75% of marks in each
Learning
Outcomes:
Good- know the
key facts in the
physics module
EBI- You can
apply what we
recap to past
paper questions
Excellent- You
can get 75% of
marks in each
question
1.
Kinetic particle theory
Learning
Outcomes:
Good- know the
key facts in the
physics module
EBI- You can
apply what we
recap to past
paper questions
Excellent- You
can get 75% of
marks in each
question
The next few slides will give
you all of the information
that you need for a question
about kinetic particle theory.
Make sure you make a note of
anything that you’re not
sure of
Learning
Outcomes:

You are going to see 3 slides with
information about the 3 states of matter.
Good- know the
key facts in the
 Translate the information you see into
physics module
your own words, so that you will be able
to remember all of the key facts.
EBI- You can
apply what we
recap to past
paper questions
Excellent- You
can get 75% of
marks in each
question
Learning
Outcomes:
Particles vibrate in a fixed position
 Strong bonds between particles
Good- know the  Particles are close together
key facts in the
physics module  Regular pattern in the arrangement
 Solids can’t be compressed as the
particles have no space to move into and
EBI- You can
they have a fixed shape as the particles
apply what we
can’t move from place to place
recap to past
paper questions
Excellent- You
can get 75% of
marks in each
question

Learning
Outcomes:
Good- know the
key facts in the
physics module
EBI- You can
apply what we
recap to past
paper questions
Excellent- You
can get 75% of
marks in each
question
Particles vibrate and move around each
other
 Weaker bonds between particles
 Particles are close together in a random
arrangement
 Liquids can’t be compressed as the
particles have no space to move into but
they can change their shape to match the
container that they are in as the
particles can move around each other

Learning
Outcomes:
Good- know the
key facts in the
physics module
EBI- You can
apply what we
recap to past
paper questions
Excellent- You
can get 75% of
marks in each
question
Particles move quickly in any direction
 No bonds between particles
 Particles are far apart
 Random pattern in the arrangement
 Gases can be compressed or squashed as
they have plenty of space to move into.
They also flow and completely fill their
container as their particles move quickly
in all directions.

Learning
Outcomes:
Good- know the
key facts in the
physics module
EBI- You can
apply what we
recap to past
paper questions
Excellent- You
can get 75% of
marks in each
question

In pairs, design a way that we could
use 7 people in order to represent
each stage of the kinetic particle
theory.

I’ll be choosing THREE pairs at
random to demonstrate their model
so make sure you ask me if you are
struggling with this task
Learning
Outcomes:
Good- know the
key facts in the
physics module
EBI- You can
apply what we
recap to past
paper questions
Excellent- You
can get 75% of
marks in each
question
Examiner’s tip
Be able to describe the
arrangement and
movement of particles in
solids, liquids and gases
solid
gas
solid
1. The marbles model act as molecules / atoms
2. Molecules leaving a liquid = evaporation OR
marbles leaving tray = evaporation
1. To evaporate the alcohol requires
energy
2. This energy (heat) is taken from the
skin and the skin feels cold
1. There are attractive forces between
molecules.
2. Only the fastest molecules have enough
energy to break away from other molecules.
3. These molecules escape from the surface
of the liquid.
4. Therefore the average speed / energy of the
remaining molecules goes down.
5. The lower the average speed / energy of
molecules the lower the temperature of the
liquid.
Learning
Outcomes:
Good- know the
key facts in the
physics module
EBI- You can
apply what we
recap to past
paper questions
Excellent- You
can get 75% of
marks in each
question
Using the examiners tip below, make your
own 6 mark question (part of it can be
multiple choice) and create your own mark
scheme that you’ll use to test someone
else in the class
“Be able to describe the arrangement and
movement of particles in solids, liquids
and gases”
 Good-
know the key facts in the physics
module
 EBI-
You can apply what we recap to past
paper questions
 Excellent-
question
You can get 75% of marks in each
Learning
Outcomes:
Good- know the
key facts in the
physics module
EBI- You can
apply what we
recap to past
paper questions
Excellent- You
can get 75% of
marks in each
question
“The three methods of heat
transfer are...”
Quickly jot down any information that you do not know
from the next 8 slides. If you are happy with the
information, try and change it into a maximum of 3
sentences
DO NOT COPY ALL OF THIS
1. Metals are good conductors
2. Non-metals and gases are poor conductors
3. Free electrons are able to move about in metals
and the part of the metal atoms that are left behind
are charged metal ions
4. These metal ions are packed closely together and
vibrate all the time
5. The hotter the metal, the faster the vibrations of the
ions
6. This kinetic energy is then transferred from the
hotter parts of the metal to the cooler parts of the
metal by the free electrons as they collide with the
ions as they move about
DO NOT COPY ALL OF THIS
1. Liquids and gases are fluids
2. When they are heated, they expand as the particles
move faster
3. The liquid or gas then becomes less dense as the
particles take up more space but they are still the
same size
4. The liquid or gas in hot areas is less dense than the
liquid or gas in cold areas, so it rises into the cold
areas.
5. The denser cold liquid or gas falls into the warm areas.
6. This cycle continues until the heat source is removed
7. The wind is caused by convection currents from the
Earth being heated by the sun
DO NOT COPY ALL OF THIS
1. All objects emit (give out) and absorb (take in)
thermal radiation (infrared radiation)
2. The hotter the object, the more infrared
radiation given off
3. Infrared radiation is a type of EM radiation so it
travels in waves and can travel in a vacuum
4. Dark, matt materials are good absorbers and
emitters of infrared radiation
5. Light, shiny materials are poor absorbers and
emitters of infrared radiation
DO NOT COPY ALL OF THIS
1. The particles in a liquid have different energies
2. Some will have enough energy to escape from
the liquid and become a gas.
3. The remaining particles in the liquid have a
lower average kinetic energy than before, so
the liquid cools down as evaporation happens.
4. This is why sweating cools you down.
5. The sweat absorbs energy from your skin so
that it can continue to evaporate.
DO NOT COPY ALL OF THIS
1. The particles in a gas have different energies.
Some may not have enough energy to remain
as separate particles, particularly if the gas is
cooled down.
2. They come close together and bonds form
between them.
3. Energy is released when this happens.
4. This is why steam touching your skin can cause
scalds: not only is the steam hot, but energy is
released into your skin as the steam condenses.
DO NOT COPY ALL OF THIS
1. Condensation happens faster if the
temperature of the gas is lowered
2. Evaporation happens faster if the liquid is
increased.
3. Evaporation happens faster if the surface
area is increased
4. Evaporation happens faster if air is moving
over the surface of the liquid
DO NOT COPY ALL OF THIS
1. Bigger temperature difference -> the faster
the heat transfer
2. Larger surface area -> the faster the heat
transfer
3. Larger volume -> the faster the heat transfer
4. Some materials either increase / decrease
heat transfer
DO NOT COPY ALL OF THIS
1. Small animals have a large surface area to
volume ratio so the lose heat quickly
2. Large animals have a low surface area to
volume ratio so lose heat slowly
3. Arctic fox has small ears to lose heat slowly
4. Fennec fox has large ears to lose heat quickly
5. Car radiators are flat with many fins so they
lose heat quickly
6. Household radiators are thin, flat, sometimes
with fins, in order to give heat to the room
quickly
Learning
Outcomes:
Good- know the
key facts in the
physics module
EBI- You can
apply what we
recap to past
paper questions
Excellent- You
can get 75% of
marks in each
question
1. Energy needed to produce evaporation comes from
the body
2. This stops the body temperature rising
1. The silver space blanket reflects
energy back to the runner
2. This reduces the energy
transferred from the body by
radiation
1. transfer of energy by waves / infrared
1. Ions gain kinetic energy
2. Energy is transferred to cooler parts of the
metal by free electrons
1. Water particles at the bottom are
heated
2. Water particles move faster
3. The warmer water expands (becomes
less dense)
4. The warm water rises / cold water falls
to take its place
1.
2.
3.
4.
5.
Know that air is an excellent insulator and
examples of insulation materials using trapped
air.
Be able to explain why evaporation causes the
surroundings to cool.
Know the factors affecting the rate at which an
object transfers energy by heating and
applications of this.
Know how the nature of a surface affects the
amount of infrared emitted.
Understand the difference between an object
emitting infrared radiation and absorbing
infrared radiation.
 Good-
know the key facts in the physics
module
 EBI-
You can apply what we recap to past
paper questions
 Excellent-
question
You can get 75% of marks in each
Learning
Outcomes:
Good- know the
key facts in the
physics module
EBI- You can
apply what we
recap to past
paper questions
Excellent- You
can get 75% of
marks in each
question
Why do we need to reduce
heat loss in the home?
HEAT AND THE HOME
In order to save money, people can change the materials
used in housing. E.g. The materials used for their
windows
Energy-saving solutions cost money to buy and install.
The payback time of an energy-saving solution is a
measure of how cost-effective it is.
Here is the equation to calculate payback time:
Payback time (years) = cost of installation (£) ÷ savings
per year in fuel costs (£)
If the payback time is too long, the energy-saving solution
is not cost-effective
1. Specific heat capacity of materials can be
found by using the formula: E = m × c × ө
2. This tells us how much energy is needed to
increase the temperature of 1kg by one
degree Celsius
3. The higher the specific heat capacity, the
more energy the material can store (e.g.
water)
4. Materials have a U-value which tells us how
well heat travels through a material
5. The lower the U-value, the better it is at
insulating
1
3 and 4 OR 1 and 2
1. U-values for the 20 mm windows are the same or higher than those for the 16
mm windows
2. So the 20 mm windows are no more energy efficient than 16 mm windows
1 and 2
1. Type B glass transmits less infrared than Type A
glass
2. As infrared has a heating effect the conservatory will
remain cooler
1.
2.
3.
4.
5.
Know that air is an excellent insulator and
examples of insulation materials using trapped
air.
Be able to explain why evaporation causes the
surroundings to cool.
Know the factors affecting the rate at which an
object transfers energy by heating and
applications of this.
Know how the nature of a surface affects the
amount of infrared emitted.
Understand the difference between an object
emitting infrared radiation and absorbing
infrared radiation.
Using the examiners tips from the
previous slide to make your own 6
mark question (part of it can be
multiple choice) and create your own
mark scheme that you’ll use to test
someone else in the class
 Good-
know the key facts in the physics
module
 EBI-
You can apply what we recap to past
paper questions
 Excellent-
question
You can get 75% of marks in each
Most Kids Hate Learning GCSE Energy Names










Magnetic
Kinetic (movement energy)
Heat (thermal energy)
Light
Gravitational potential
Chemical
Sound
Electrical
Elastic potential
Nuclear
Wasted
Input
Useful
Wasted
Input
Useful
Wasted
Input
Useful
Wasted
Input
Useful
Wasted
Input
Useful
The thickness of each arrow is drawn to scale
to show the amount of energy
Notice that the total amount of energy
before is equal to the total amount of energy
after (conservation of energy)
Although the total energy out is the same,
not all of it is useful.
Efficiency is defined as
Efficiency (%) = useful energy output x 100
total energy input
 The
closer the efficiency is to 1 or 100%, the
more efficient the device is and the less
energy it wastes
 No device will have an efficiency of 1 or
100% as some energy is always lost as heat
to the surroundings
Efficiency =
75 x 100 = 15%
500
A
100J kettle that wastes 10% of it’s energy as
sound and 20% energy as heat
A
200J iPod that wastes 10% of it’s energy as
heat
A
400J iPod that has 60% useful sound and light
energy
Why use energy efficient devices?
We need to use energy efficient devices as
they use less energy to do the same job when
compared to less energy efficient devices.
Why do you think this is a good thing?
1. Save money
2. Less energy resources are used so there will
be more for the future
3. Less CO2 is produced so the effect of global
warming will be decreased
1. 120 / 200 =
2. 0.6 or 60%
1. More efficient, so less energy / electricity needed
2. Less fuel burned so less CO2 produced
1. You could turn the sound up or down
2. You could turn the brightness up or down
1. Most energy out as light or least energy wasted as heat
14 squares
25 squares
3 squares
8 squares
1. 22
1. 28 / 50 * 100
2. = 56%
1.
2.
3.
4.
Energy = power × time
Power = 0.85 kW, time = 0.1
Energy = 0.085
kWh
Learning
Outcomes:
Good- know the
key facts in the
physics module
EBI- You can
apply what we
recap to past
paper questions
Excellent- You
can get 75% of
marks in each
question
Examiner’s tip
Know how to use the equation and calculate
the efficiency either as a decimal or as a
percentage.
Understand why a device or process can never
be greater than 100% efficient.
Understand the term ‘pay-back’ time in
relation to heating and insulating buildings.
Using the examiners tips on the previous
page to make your own 6 mark question
(part of it can be multiple choice) and
create your own mark scheme that you’ll
use to test someone else in the class
“Be able to describe the arrangement and
movement of particles in solids, liquids
and gases”
 Good-
know the key facts in the physics
module
 EBI-
You can apply what we recap to past
paper questions
 Excellent-
question
You can get 75% of marks in each
Learning
Outcomes:
Good- know the
key facts in the
physics module
EBI- You can
apply what we
recap to past
paper questions
Excellent- You
can get 75% of
marks in each
question
1.
Generating electricity
4
5
3
2
1
1. Fossil fuel is burnt
2. The heat turns water to
steam
3. The steam turns a turbine
4. The turbine turns a generator
5. This induces a current and
creates electricity
Electricity from a power station goes to:
1. Step-up transformers – increases the voltage which
decreases the current and reduces energy loss
2. High voltage transmission lines
3. Step-down transformers – decrease the voltage to
make it safe for us to use
4. Consumers, for example homes, factories and shops.
All of these methods are used to heat water to create
steam which is used to turn the turbine and generate
electricity
Energy source
Advantages
Disadvantages
Coal
Relatively cheap to
mine, ready made
fuels
Non-renewable,
burning produces
CO2
Oil
Short start-up time,
ready made fuels
Non-renewable,
burning produces
CO2
Gas
Slightly cleaner fuel than Non-renewable,
oil and gas and is a ready burning produces
made fuel
CO
2
Nuclear power
Produces lots of
energy, does not
produce CO2
Non-renewable,
produces dangerous
nuclear waste
1. Wind, hydroelectricity and geothermal all turn a
turbine which will create electricity
2. Solar cells use light to create electricity
Energy source
Advantages
Disadvantages
Wind
Renewable, no fuel
costs
No wind sometimes,
noisy
Hydroelectric
Renewable, no fuel
costs
Can flood areas,
disrupts habitats
Solar
Renewable, no fuel
costs
No sun at night, some
countries don’t get
enough sun in the
day, panels are
expensive
Geothermal
Renewable, no fuel
costs
Only available in
volcanic regions,
Power stations fuelled by fossil fuels or nuclear fuels are reliable
sources of energy. This means they can provide power
whenever it is needed.
1.
2.
3.
4.
gas-fired station (shortest start-up time)
oil-fired station
coal-fired station
nuclear power station (longest start-up time)
Nuclear power stations and coal-fired power stations provide
'base load' electricity - run all the time as they take the longest
time to start up.
Oil-fired and gas-fired power stations are often used to provide
extra electricity at peak times, because they take the least time
to start up.
The fuel for nuclear power stations is relatively cheap, but the
power stations themselves are expensive to build. It is also very
expensive to dismantle old nuclear power stations and to
store their radioactive waste, which is a dangerous health hazard.
Boiler
Generator
6 squares
20 squares
14 squares
1. Useful / input
2. 6 / 20 = 0.3 or 30%
Generator
Nuclear fission
Learning
Outcomes:
Good- know the
key facts in the
physics module
EBI- You can
apply what we
recap to past
paper questions
Excellent- You
can get 75% of
marks in each
question
Wave energy - the rise and fall of the water
(kinetic energy) drives generators and makes
1. Be able to draw and label a block diagram of a
electricity
power station showing the main parts.
2. Be
able to– distinguish
the goes
difference
between
Tidal
energy
when the tide
in and
out,
and tides.
therewaves
is a large
amount of kinetic energy. This
3. Be
able toadescribe
the advantages
and
goes
through
tidal barrage
that contains
disadvantages
of solarelectricity
cells.
generators
which makes
4. Understand that to prevent carbon dioxide
building
up inand
thestorage
atmosphere
can catch
it
Carbon
capture
stopswe
carbon
dioxide
and up
store
of the best
natural containers
building
in it.
theSome
atmosphere.
It involves
are old carbon
oil and gas
fields.
separating
dioxide
from waste gases. The
5. Be able
to identify
label
a diagram offor
the
carbon
dioxide
is then and
stored
underground,
main in
parts
National
example
old of
oil the
fields
or gasGrid.
fields.
Learning
Outcomes:
Good- know the
key facts in the
physics module
EBI- You can
apply what we
recap to past
paper questions
Excellent- You
can get 75% of
marks in each
question
We can calculate the amount
of electrical energy
transferred by an appliance
and how much it costs to run.
This is useful for comparing
the advantages and
disadvantages of using
different electrical
appliances
E
=P×t
 E - energy transferred in kWh / J
 P - power in kW
 T - time in h.
 Power is sometimes measured in kWh. To
convert from W to kW you must divide by
1,000.
 E.g. 2,000 W = 2,000 ÷ 1,000 = 2 kW.

Electricity meters measure the number of units of
electricity used. The more units used, the greater
the cost.
total cost = number of units × cost per unit

E.g. if 5 units of electricity are used at a cost of 8p
per unit, the total cost will be
5 × 8 = 40p

The number of units used can be calculated using
this equation:
total cost = power (kW) × time (h) × cost per unit
Learning
Outcomes:
Good- know the
key facts in the
physics module
EBI- You can
apply what we
recap to past
paper questions
Excellent- You
can get 75% of
marks in each
question
 Know
the units of each term in the equation.
 Know
how to convert power from watts to
kilowatts and vice versa.
 Know
how to convert time from hours to
minutes and seconds and vice versa, and be
careful to make these conversions in an exam if
necessary.
Using the examiners tip below, make your
own 6 mark question (part of it can be
multiple choice) and create your own mark
scheme that you’ll use to test someone
else in the class
“Be able to calculate the cost of electricity
and rearrange the formula and change
units when necessary”
1. acid rain
2. global warming/greenhouse effect
1. Removal of exhaust gases
2. Use alternative source not producing CO2
1. E = 5 × 108 × 3600 × 24 J/day
2. × 4 (for 4 generators)
3. P × t = 1.73 × 1014 (J/day)
2.66 × 1010 × 18 829 = 4.86 × 1014
1. useful/input
2. 1.73/4.86
3. 0.36 or 36%
1.
2.
3.
4.
5.
boiler – heat to surroundings
turbine – not all steam energy
used/heat/sound lost to surroundings
generator – heat in wires/coils/heat to surroundings
transformer – heat in wires/coils/heat to
surroundings
1. Energy spread out/diluted
2. As surroundings become warmer/energy lost as
heat
 Good-
know the key facts in the physics
module
 EBI-
You can apply what we recap to past
paper questions
 Excellent-
question
You can get 75% of marks in each
Learning
Outcomes:
Good- know the
key facts in the
physics module
EBI- You can
apply what we
recap to past
paper questions
Excellent- You
can get 75% of
marks in each
question
1.
Waves
 Waves
are vibrations that transfer energy
from place to place without matter (solid,
liquid or gas) being transferred.
 Some
waves must travel through a
substance. The substance is known as the
medium and it can be solid, liquid or gas.
 In
transverse waves, the oscillations
(vibrations) are at right angles to the
direction of travel and energy transfer
 Light
and other types of electromagnetic
radiation are transverse waves. All types of
electromagnetic waves travel at the same
speed through a vacuum, such as through
space.
 In
longitudinal waves, the oscillations are
along the same direction as the direction of
travel and energy transfer.
 Sound
waves and waves in a stretched
spring are longitudinal waves.
 The
wavelength of a wave is the distance
between a point on one wave and the same
point on the next wave.

The frequency of a wave is the number of
waves produced by a source each second. It is
also the number of waves that pass a certain
point each second.
 The
speed of a wave is related to its frequency
and wavelength, according to this equation:
v=f×λ
v
is the wave speed in metres per second, m/s
 f is the frequency in hertz, Hz
 λ (lambda) is the wavelength in metres, m.
1. speed = frequency × wavelength
1. 300, 000,000 / 909 000
2. = 330m
A
W
W
1. 0.1m X 2Hz
2. 0.2m/s
The angle of incidence equals the angle of reflection
 Sound waves and light waves reflect from surfaces.
 Smooth surfaces produce strong echoes when sound
waves hit them, and they can act as mirrors when
light waves hit them. The waves are reflected
uniformly and light can form images

Rough surfaces scatter sound and light in all
directions. However, each tiny bit of the surface still
follows the rule that the angle of incidence equals
the angle of reflection
Sound waves and light waves change speed when
they pass across substances with different densities.
 This causes them to change direction and this effect
is called refraction.
 Refraction doesn't happen if the waves cross the
boundary at an angle of 90°(the normal) - they carry
straight on.

When waves meet a gap in a barrier, they carry on
through the gap and spread out
 How much they spread out depends on how the width
of the gap compares to the wavelength of the waves.
 Lots of diffraction happens when the wavelength is
the same size as the gap.

A gap similar to the wavelength causes a lot of
spreading with no sharp shadow, e.g. sound through a
doorway
 A gap much larger than the wavelength causes little
spreading and a sharp shadow, e.g. light through a
doorway.

Sound waves and light waves change speed when
they pass across substances with different densities.
 This causes them to change direction and this effect
is called refraction.
 Refraction doesn't happen if the waves cross the
boundary at an angle of 90°(the normal) - they carry
straight on.

The normal
v
light has moved from glass to air / from air to glass
value of v doubles but the
value of y does not double
As (angle) v increases, angle y increases
no evidence outside this range
Longitudinal waves
 Echoes are reflections of sound waves
 Sound can only travel in a solid, liquid or gas
 A loud sound has a high amplitude
 A quiet sound has a small amplitude
 A high pitched sound has a high frequency
 A low pitched sound has a low frequency
 The normal range of human hearing is between about
20 Hz and 20 kHz
 The range becomes less as we get older.
 Sounds with frequencies above about 20 kHz are
called ultrasound.

Microphone
Loud speaker
Radio waves
Electrical vibrations
Light waves
It will go quieter
Contains 7 different types of radiation
Longest wavelength
Shortest frequency
Shortest wavelength
Highest frequency
Used for TV and radio
 TVs use higher frequencies than radios
 Diffraction allows radio signals to be received
behind hills and repeater stations are used to
improve reception

Used to transmit signals such as mobile phone calls.
 Microwave transmitters and receivers on buildings
and masts communicate with the mobile telephones
in their range.

Some mobile phones may be a
health risk.
 Others think that the intensity of
the microwaves is too low to
damage tissues by heating, and
microwaves are not ionising.
 Some wavelengths can be used to
transmit information to and from
satellites in orbit. Satellite TV
signals use microwaves.

VISIBLE LIGHT
Visible light helps us to communicate via sight
 Cameras and video recorders use visible light
 Very bright light damages our eyes

INFRARED
Infrared is used in toasters,
heaters and grills and can cause
burns
 Used in burglar alarms, remote
controls and security alarms

Examiner’s tip
 Be
able to construct a ray diagram to show the
image formed by a plane mirror.
 Know the order of the electromagnetic waves
within the spectrum in terms of energy,
frequency and wavelength.
 Be able to complete diagrams for wave fronts
showing reflection, refraction and diffraction.
 Learn the units of the terms in the equation and
know how to convert kilohertz to hertz.
 Know how radio waves, microwaves, infrared and
visible light can be used in communications.
 Know the relationship between pitch and
frequency.
to compare mobile phone usage
between the two groups
enough data to indicate relationship
or reduce effect of anomalous data
1. Research may be biased (in favour of
companies)
2. Negative effects on health may not get
published
1. It allows people to easily identify lower
risk phones
2. And this allows people to make a more
informed choice
Learning
Outcomes:
Good- know the
key facts in the
physics module
EBI- You can
apply what we
recap to past
paper questions
Excellent- You
can get 75% of
marks in each
question
Using the examiners tip on the previous slide
to make your own 6 mark question (part of
it can be multiple choice) and create your
own mark scheme that you’ll use to test
someone else in the class
 Good-
know the key facts in the physics
module
 EBI-
You can apply what we recap to past
paper questions
 Excellent-
question
You can get 75% of marks in each
Learning
Outcomes:
Good- know the
key facts in the
physics module
EBI- You can
apply what we
recap to past
paper questions
Excellent- You
can get 75% of
marks in each
question
1.
Origins of the Universe
Learning
Outcomes:
Good- know the
key facts in the
physics module
EBI- You can
apply what we
recap to past
paper questions
Excellent- You
can get 75% of
marks in each
question
The next few slides will give
you all of the information
that you need for a question
about the origins of the
Universe.
Make sure you make a note of
anything that you’re not
sure of
Learning
Outcomes:
Good- know the
key facts in the
physics module
EBI- You can
apply what we
recap to past
paper questions
Excellent- You
can get 75% of
marks in each
question
Examiner’s tip
Be able to explain the
term ‘red-shift’ and the
‘Big Bang’ theory.
 Theory
– an idea but not a fact
 The theory states that originally all the matter
in the universe was concentrated into a single
incredibly tiny point.
 This began to enlarge rapidly in a hot explosion
(called the Big Bang), and it is still expanding
today.
 The Big Bang happened about 13.7 billion years
ago
 Cosmic
microwave background radiation (CMBR)
– thought to be left over heat from the original
explosion
 Doppler
effect
 Red-shift
When a police car goes past, its siren is high-pitched
as it comes towards you, then becomes low-pitched
as it goes away.
 When a source (e.g. galaxy) moves towards an
observer, the observed wavelength decreases and the
frequency increases.
 When a source (e.g. galaxy) moves away from an
observer, the observed wavelength increases and the
frequency decreases.


When an object (e.g. galaxy) moves away from an
observer, its light is affected by the Doppler effect

We know our sun has helium in it because there are
black lines in the spectrum of the light from the Sun
where helium has absorbed light. These lines form the
absorption spectrum for helium.

When we look at the spectrum of a distant star, we still
see an absorption spectrum. However, the pattern of
lines has moved towards the red end of the spectrum,
as you can see above.

The positions of the lines have changed because of
the Doppler effect. Their wavelengths have increased
and their frequencies have decreased.

The further from us a star is, the more its light is
red-shifted. This tells us that distant galaxies are
moving away from us, and that the further away a
galaxy is, the faster it's moving away.

Red shift tells us how far away a galaxy is and the
speed at which it is getting further away from us
1. Distance from Earth
2. Speed stars / galaxies are
moving (away from Earth)
3. Supports theory that the
Universe is expanding / Big Bang
theory
1. The microwave radiation comes from
radiation present just after Big Bang
2. The Big Bang theory is currently the only way
of explaining CMBR
1. wavelength is decreased and frequency
increased
1. Big bang theory – universe started at
one point then expanded
2. Steady state theory – universe has no
origin / has always existed
1. Wavelength of light increases / frequency of light
decreases
2. or wavelength / light moves to red end of spectrum
1. Red-shift is evidence / supports idea of
expanding universe
2. Both theories use the idea / accept / explain why
the universe is expanding
1. to find evidence to support one or both
theories or to find evidence to disprove one
or both theories
1. Religious belief or no / insufficient evidence
Learning
Outcomes:
Good- know the
key facts in the
physics module
EBI- You can
apply what we
recap to past
paper questions
Excellent- You
can get 75% of
marks in each
question
Using the examiners tip below, make your
own 6 mark question (part of it can be
multiple choice) and create your own mark
scheme that you’ll use to test someone
else in the class
“Be able to explain the term ‘red-shift’
and the ‘Big Bang’ theory.”