Download P2 Revision Document 2013

GCSE
Core Gateway Science B
P2: Living for the Future
(Energy resources)
“We are what we
repeatedly do. Excellence,
therefore, is not an act
but a habit”
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Unit
Page
Completed By

2a
2b
2c
2d
2e
2f
2g
2h
Use the activities and past exam questions in this booklet to plan and
support your revision ready for the B2C2P2 science exam.
REVISION WEBSITE – The following website is available for you to use to
support your revision and help you answer the exam questions in this revision
guide
http://www.bbc.co.uk/schools/gcsebitesize/science/ocr_gateway/
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P2a: Collecting energy from the Sun
Grade E

Understand the properties
of photocells.
Recall that DC electricity is
current in the same
direction all the time.
Describe how the Sun’s
energy can be harnessed.
Grade C

Describe the advantages and
disadvantages of photocells.
Describe advantages and
disadvantages of wind
turbines.
Grade A
Describe how light produces
electricity in a photocell.
Describe the factors
determining the current and
power produced in a
photocell.
Explain why passive solar
heating occurs.
Recall that an efficient solar
collector nust track the Sun
across the sky.
Key Information
Photocells are devices that transfer light energy directly into electrical energy. They produce DC direct current - electricity. This is electricity in which the current moves in the same direction all the
time.
Photocells have no moving parts. They do not need to be connected to the National Grid, so no cables
are needed and they can work in remote locations. For example, they are used to power the lights for
some road signs.
The output of photocells depends on the surface area that is exposed to light. For a given light
intensity, the larger the area, the greater the power output.
Photocells consist of two types of silicon crystal. When light energy is absorbed by the silicon:
negatively charged electrons are knocked loose from the silicon atoms in the crystal the electrons
flow freely, creating an electric current.(Higher Tier)
Revision Ideas
1. Draw a mind map for the P2 unit. Add pictures and colour
code key words and information
2. Write some practice exam questions for other students
to try, make sure you write a mark scheme.
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QWC Question (6 marks)
When answering a QWC question remember the following points: Use correct science vocabulary, organise ideas,
avoid using “it”, and write in full sentences. You also need to try and keep you answer relevant to the question. A
good way to do all this is to write out important key vocabulary and then use them to structure your answer.
Underlining them will help you keep track and highlight to the examiner your good use of key terms,
Question – This question is photocells
The solar sunFLOWER™ lamp is used to light a footpath.
Photocells on top of the lamp transfer light energy from the Sun into electricity.
This energy is stored in a battery to light a bulb when it gets dark.Write down one advantage of
using photocells to produce electricity.The sunFLOWER™ is shaded by trees.Why is its power
reduced? Describe how light from the Sun produces electricity in a photocell.
In your answer, use ideas about
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•
energy
•
atoms
•
electrons.
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Important words list
Direct Current
surface area
Photocell
Electrons
Silicon atoms
Crystal
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P2b: Generating Electricity
Grade E

Describe how movement of a
coil or magnet generates
electricity by means of the
dynamo effect.
Recall that a generator
produces Alternating
Current AC.
Recall that a battery
produces Direct Current DC.
Describe the main stages in
the production and
distribution of electricity.
Recognise energy waste in a
simple power station.
Use the energy efficiency
equation.
Grade C

Describe and recognise ways
to increase the dynamo
effect.
Describe and interpret AC
using a voltage / time graph.
Describe how simple AC
generators work.
Describe how electricity is
generated at a conventional
power station.
Grade A
Use the energy efficiency
calculation to calculate
useful energy output, total
energy input or wasted
energy.
Key Information
Most of our electricity is generated in power stations by
burning fuels. You need to know and understand how power
stations work and how electricity is transported to our homes
and factories.
Revision Ideas
1. Draw a diagram of a Power Station. Label all the places
where energy is being lost and how this loss is
minimised.
2. Name two energy sources that are burned as fuels in a
Power Station; one renewable and one non-renewable.
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QWC Question (6 marks)
When answering a QWC question remember the following points: Use correct science vocabulary, organise ideas,
avoid using “it”, and write in full sentences. You also need to try and keep you answer relevant to the question. A
good way to do all this is to write out important key vocabulary and then use them to structure your answer.
Underlining them will help you keep track and highlight to the examiner your good use of key terms,
Question – This question is about Generating electricity
Wind turbines are often located in groups on wind farms.
The energy of the wind can be transferred into electrical energy by the turbines.
Describe how electricity is generated by the turbines. Explain how the current from a generator
can be increased.
Important words list
Generator
Alternating current
Dynamo effect
Coil
Magnet
Magnetic field
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P2c: Global Warming
Grade E

Understand that gases in
the atmosphere prevent heat
radiating into space
Recall and recognise this as
the greenhouse effect.
Recall and identify
greenhouse gases.
Describe reasons for climate
change caused by global
warming.
Describe difficulties of
measuring Global warming.
Explain why climate
scientists should share data.
Grade C

Describe how certain
electromagnetic wavelengths
are absorbed by gases in the
atmosphere.
Recall and identify natural
and man-made sources of
greenhouse gases.
Describe scientific evidence
for and against the idea of
man-made global warming.
Distinguish between opinion
and evidence based
statements about global
warming.
Grade A
Explain the greenhouse
effect.
Explain how scientists can
agree about the greenhouse
effect, but disagree about
whether human activity is
affecting global warming.
Key Information
There is a large amount of discussion amongst scientists,
politicians and the general public about the reasons for global
warming. The greenhouse effect is considered to be a proven
scientific explanation. Discussions will continue as more evidence
and sources are published and shared with the Science community
who then in turn have to communicate complex scientific issues to
the wider population.
Revision Ideas
The greenhouse effect
Produce a leaflet explaining the greenhouse effect.
Global Warming
Write a letter that supports the idea that human activity is causing global
warming.
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QWC Question (6 marks)
When answering a QWC question remember the following points: Use correct science vocabulary, organise ideas,
avoid using “it”, and write in full sentences. You also need to try and keep you answer relevant to the question. A
good way to do all this is to write out important key vocabulary and then use them to structure your answer.
Underlining them will help you keep track and highlight to the examiner your good use of key terms,
Question – This question is about global warming and the greenhouse effect.
Some scientists believe that increased CO2 levels arising from the combustion of hydrocarbons lead to global
warming because CO2 is a greenhouse gas. Carbon capture and storage, CCS, is being developed as a method for
removing CO2 produced by combustion. Different gases have different contributions to global warming. State two
factors that affect the contribution of a greenhouse gas to global warming. There is much international concern that
an increase in atmospheric concentration of carbon dioxide and methane may lead to global warming and climate
change.
(a) Carbon dioxide and methane are both greenhouse gases
(i) What type of radiation is absorbed by methane molecules and what effect does this radiation have on these
molecules?
Suggest why some scientists are more concerned about carbon dioxide as a greenhouse gas than methane
Carbon dioxide is a greenhouse gas that has been linked to climate change. What happens within a carbon dioxide
molecule when it absorbs infrared radiation?
(6marks)
Important words list
Carbon dioxide gas
Combustion
Fuel
Absorb
Radiation
Greenhouse gases
Methane
Global warming
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P2d: Fuels for Power
Grade E
Grade C

Recall that the unit of Power
is the watt or kilowatt.
Understand that the cost of
using electrical appliances
depends on their Power and
the time they are used for.
Use the Power equation to
calculate the Power of an
appliance.
Recall the use of
transformers to increase or
decrease voltage.

Use the Power equation to
calculate the Power of an
appliance, including
conversion of units of Power.
State that the unit of
electrical energy supplied is
the kilowatt hour.
Calculate the number of
kilowatt hours given the
Power and the time used.
Use the energy supply
equation to calculate energy
supplied.
Calculate the cost of energy
supplied.
Grade A
Use and manipulate the
Power equation.
Use the kilowatt hour as a
measure of energy supplied.
Describe the advantages and
disadvantages of using off
peak electricity in the home.
Explain how an increased
voltage reduces current,
thus decreasing the energy
lost from cables as heat.
Key Information
Fuels are energy sources that release heat energy during burning. The three common fuels
used in power stations are fossil fuels; renewable biomass (wood, straw, and manure); Nuclear
fuels – uranium mostly but sometimes Plutonium.
Power = voltage x current
Energy supplied = power x time
Revision Ideas
1. Draw simple diagram of the National Grid and label it
showing the following; power station; step up and step
down transformers; pylons; consumer.
2. Produce some flash cards for the key words underlined in
the text above ( word or equation on one side and
definition or how equations are used).
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QWC Question (6 marks)
When answering a QWC question remember the following points: Use correct science vocabulary, organise ideas,
avoid using “it”, and write in full sentences. You also need to try and keep you answer relevant to the question. A
good way to do all this is to write out important key vocabulary and then use them to structure your answer.
Underlining them will help you keep track and highlight to the examiner your good use of key terms,
Question – This question is about producing electricity in power stations (6marks)
Electricity is produced by Power Stations. Describe briefly how Power Stations use different
energy sources to do this, identifying three named energy sources.
Electrical energy leaves a Power station through a transformer. Describe how and why
transformers are used by the National Grid.
If a generator in a Power Station produces a voltage of 20,000 V it will generate a current of
60 A.Calculate the Power output of this generator.
Important words list
Power Station
Fuels
Renewable and nonrenewable fuels
Power
National Grid
Transformers
Step up / Step down
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P2e: Nuclear radiations
Grade E

Recognise beneficial and
harmful effects of radiation.
Recall the 3 types of nuclear
radiation.
Understand that nuclear
radiation causes potentially
harmful ionisation.
Describe how to handle
radioactive materials safely.
Describe nuclear waste as
radioactive and harmful, but
not responsible for Global
warming.
Grade C

Describe examples of
beneficial uses of radiation.
Understand that radioactive
materials give out radiation
over time.
Describe the relative
penetrating power of alpha,
beta and gamma radiations.
Understand that nuclear
radiation can form positive
ions when atoms lose
electrons.
Understand that nuclear
radiation can for negative
ions when atoms gain
electrons.
Recall that Uranium is a nonrenewable resource.
Recall that Plutonium is a
nuclear waste product and
can be used to make nuclear
bombs.
Describe methods of
disposing of radioactive
waste.
Grade A
Explain how ionisation can
damage the DNA in human
cells.
Describe the advantages and
disadvantages of nuclear
power.
Explain the problems of
dealing with radioactive
waste.
Key Information
The 3 types of radiation are alpha, beta and gamma. They each have different
penetrating powers.
Revision Ideas
1. Make some true / false statements cards. Practice sorting them into true/false piles.
Time yourself and see if you can beat it the next day.
2. Write a script for a “TV drama” where the characters are concerned about the dangers
from a new Nuclear Power Station being situated near their homes
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QWC Question (6 marks)
When answering a QWC question remember the following points: Use correct science vocabulary, organise ideas,
avoid using “it”, and write in full sentences. You also need to try and keep you answer relevant to the question. A
good way to do all this is to write out important key vocabulary and then use them to structure your answer.
Underlining them will help you keep track and highlight to the examiner your good use of key terms,
Question – This question is about infrared and microwave cookery.
Alpha, beta and gamma radiations all have different properties. Describe their penetrating
powers and use these to explain how each type of nuclear radiation can be used.
Describe the advantages and disadvantages of nuclear power. (6marks)
Important words list
Alpha, beta, gamma
Nuclear radiation
Penetrating power
Lead, aluminium, paper
Negative ions, positive
ions
Electrons
Ionisation
Uranium
Plutonium
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P2f: Exploring our Solar System
Grade E

Identify the relative
positions of the Earth,
Sun and planets.
Recall the make-up of
the Universe.
Explain why stars give
off light and can be seen
over long distances.
Recall that radio signals
take a long time to travel
through the Solar
System.
Compare the resources
needed by manned and
unmanned spacecraft.
Describe why unmanned
spacecraft are sent into
space.
Grade C

Recall the relative
nature and size of the
features of the
Universe.
Describe a light-year.
Describe the difficulties
of manned space travel
between planets.
Recall that unmanned
spacecraft can
withstand conditions
lethal to humans.
Compare how
information from space
is returned to Earth
from different
distances.
Grade A
Recall that circular
motion requires a
centripetal force.
Understand that
gravitational attraction
provides the centripetal
force for orbital motion.
Explain why a light-year
is a useful unit for
measuring long distances.
Explain the advantages
and disadvantages of
using unmanned
spacecraft.
Key Information
When we look at the night sky we can sometimes see the Moon, artificial
satellites, planets in our Solar System and the billions of stars which make up
the Universe.
Revision Ideas
1. Produce a revision card on the relative positions, sizes and
nature of planets, stars, comets, meteors, galaxies and
black holes.
2. Make an information leaflet describing, explaining and
comparing the differences between manned and
unmanned spacecraft.
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QWC Question (6 marks)
When answering a QWC question remember the following points: Use correct science vocabulary, organise ideas,
avoid using “it”, and write in full sentences. You also need to try and keep you answer relevant to the question. A
good way to do all this is to write out important key vocabulary and then use them to structure your answer.
Underlining them will help you keep track and highlight to the examiner your good use of key terms,
Question – This question is about Exploration of our Solar System
The first spacecraft to visit the Moon were unmanned robots. By 1969, humans had landed on the Moon.
(a)
Suggest two reasons why manned spacecraft are not used to explore other planets?
(b)
It costs a large amount of money to send spacecraft to other planets. Scientists often have to
persuade governments that this is a good way to spend money.
Suggest two reasons scientists might give to persuade governments that it is worthwhile.
(c) Compare how information from space is returned to Earth from different distances.
. (6marks)
Important words list
Reflection
Speed of light
Long distances
Manned and unmanned
spacecraft
Stars, planets, comets,
meteors, galaxies and
black holes.
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P2g: Threats to Earth
Grade E

Understand the origins
of the Moon.
Recall that large
asteroids have collided
with the Earth in the
past.
Recall that asteroids are
rocks.
Describe the
consequences of a
collision with a large
asteroid.
Describe the make-up of
a comet.
Describe a Near Earth
Object (NEO).
Describe how NEO’s may
be seen.
Grade C

Describe how a collision
between two planets can
result in an Earth-Moon
system.
Describe the origin and
orbit of asteroids.
Describe evidence for
past asteroid collisions.
Describe the origin and
orbit of comets.
Describe how the speed
of a comet changes as it
approaches a star.
Describe how
observations of NEOs
are used to determine
their trajectories.
Explain why it is difficult
to observe NEOs.
Grade A
Discuss evidence for the
Earth-Moon system as a
result of a collision
between two planets.
Explain the location of
the asteroid belt.
Explain why the speed of
a comet changes as it
approaches a star.
Suggest and discuss
possible actions to
reduce the threat of
NEOs.
Key Information
Most people ignore the threat of asteroids collisions with Earth. This section shows that the
threat is real and has proved to be lethal many times in the past. An understanding of what is
and can be done to avoid such collisions in the future.
Revision ideas;
1. Research evidence that can be used to explain the
extinction of the dinosaurs.
2. Do a comparison of asteroids and comets, showing their
similarities and differences.
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QWC Question (6 marks)
When answering a QWC question remember the following points: Use correct science vocabulary, organise ideas,
avoid using “it”, and write in full sentences. You also need to try and keep you answer relevant to the question. A
good way to do all this is to write out important key vocabulary and then use them to structure your answer.
Underlining them will help you keep track and highlight to the examiner your good use of key terms,
Question – This question is about threats to Earth.
Scientists think that the Earth-moon system was caused by the collision of two planets. What evidence
is there that this is how the Earth and Moon were made?
There is an asteroid belt between Mars and Jupiter. In the past some asteroids have collided with
Earth.
Describe some evidence for these collisions.
What are NEOs? Why/how do scientists study them?
(6marks)
Important words list
Collision
Orbit
Asteroids
Evidence
NEO
Crater
Hot rocks
Climate change
Extinction
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P2h: The Big Bang
Grade E

Describe the Big Bang
Theory for the origin of
the Universe.
Recall the properties of
stars.
Understand that not
even light can escape
from Black Holes.
Recognise change in
accepted models of the
size and shape of the
universe over time.
Describe and recognise
the Ptolemaic and
Copernican models and
how they differ from
each other and the
modern day model of the
universe.
Grade C

Recall the movement of
galaxies away from
Earth.
Recall that microwave
radiation is received
from all parts of the
universe.
Describe the end of the
lifecycle of a small star
and a large star.
Describe the evidence or
observations behind
Copernicus and Galileo’s
new models of the
Universe.
Explain how technological
advances contributed to
the new models.
Grade A
Explain how the Big Bang
Theory accounts for redshift in more distant
galaxies.
Explain how the Big Bang
Theory accounts for the
age and starting point of
the Universe.
Describe the life history
of a star.
Explain the properties of
a black hole.
Explain why Copernicus
and Galileo’s new models
were considered
controversial.
Key Information
There are a number of theories about how the Universe was formed and how it
will continue to evolve. This section develops ideas about the evolution of the
Universe and it’s possible future. The Big Bang theory is considered as the most
recent theory to explain how the Universe was formed.
Revision Ideas
1. Draw a picture showing end of the life ‘cycle’ of small and large
stars . Cut it up and make it into a jigsaw puzzle.
2. Produce a timeline for the changing models of the Universe.
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QWC Question (6 marks)
When answering a QWC question remember the following points: Use correct science vocabulary, organise ideas,
avoid using “it”, and write in full sentences. You also need to try and keep you answer relevant to the question. A
good way to do all this is to write out important key vocabulary and then use them to structure your answer.
Underlining them will help you keep track and highlight to the examiner your good use of key terms,
Question – This question is about the Big Bang Theory
People often think about how the Universe and stars began.
One theory that explains the start of the Universe is the Big Bang.
The Big Bang theory helps us to understand the movement of galaxies.
(a)
What does the Big Bang theory tell us about the movement of nearby galaxies?
(b)
What does the Big Bang theory tell us about the movement of distant galaxies?
(c)
Scientists have detected microwave radiation reaching the Earth.
This radiation started soon after the Big Bang.
Where does this radiation come from?
(6marks)
Important words list
Big Bang theory
Stars
Galaxies
Microwave radiation
Universe
Expanding
Spectrum
Red shift
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