Name: ........................................................
Class Teacher: ........................................................
Module P4:
Radiation for Life
Revision Booklet for Examination 18th June 2010
P4a: Sparks
Revision Activity 1: use traffic lighting to highlight the areas that you need to revise and
then tick them off in the boxes once you have.
Learning objectives
High Demand:
Low Demand:
Describe and recognise that
insulating materials can become
charged when rubbed with
another insulating material.
State that there are two kinds
of charge:
★positive
★negative
Low Demand:
Describe static electricity in
terms of the movement of
electrons:
★a positive charge do to
the lack of electrons;
★a negative charge due to
an excess of electrons.
Standard Demand:
Describe and recognise that
when some materials are rubbed
that attract other objects:
★small pieces of paper or
cork to a rubbed comb or
strip of plastic
★certain types of dusting
brushes become charged
and attract dust as they
pass over it.
State and recognise that like
charges repel and unlike charges
attract.
State and recognise that
electrostatic phenomena are
caused by the transfer of
electrons.
Low Demand:
Standard Demand:
Recognise and describe how
you can get an electrostatic
shock from charged objects:
★synthetic clothing
Recognise and describe how
you can get an electrostatic
shock if you become charged
and then Earthed:
★touching water pipes
after walking on a floor
with an insulating material.
e.g. vinyl.
Explain how static electricity
can be dangerous when:
★in atmospheres where
explosions could occur eg
inflammable gases or
vapours or with high
concentrations of oxygen;
★in situations where large
quantities of charge could
flow through the body to
earth.
Explain how static electricity
can be a nuisance:
★dirt and dust attracted to
insulators (plastic
containers, TV monitors
etc);
★cause clothing to “cling”.
High Demand:
Explain how the chance of
recieving an electric shock can
be reduced by:
★correct earthing;
★use of insulating mats;
★using shoes with
insulating soles.
Explain why it is necessary to
earth lorries containing
inflammable gases and liquids
and powders before unloading.
Explain how anti-static sprays,
liquids and cloths help reduce
the problems of static electricity.
Activity 2: Make some revision cards highlighting the key points.
Question 1: Cloze Activity:
Fill in the gaps in the following sentences:
electrons
charge
same
rubbing
attract
repel
positively
moving
neutrons
repel
attract
_________ a polythene rod gives it static electricity.
Static means not _______.
Atoms contain negatively charged particles called ___________ , __________ charged
particles called protons and neutral particles called _____________.
When charged objects are brought near each other, they either__________ or
___________ each other.
What happens depends on their _____________.
Two objects with the __________ charge will __________ each other, whilst oppositely
charged objects will ____________ each other.
Question 2:
(a)
steel, cotton, nylon, paper, copper, perspex, rubber, carbon
From the list of materials above, select:
i. two good insulators
ii.a material which is neither a good insulator nor a good conductor
iii.two good conductors
(b)
Glass wool and the human body will all conduct electricity to some extent.
What do they all each contain that makes it possible for them to do this?
Question 3:
Two light, conducting balls are suspended on nylon threads of equal length.
Describe and explain what would happen to balls in each of the following circumstances:
(a)
the balls are equally charged and both carry the same charge.
(b)
the balls are equally charged with opposite charges.
(c)
one ball is charged and the other is not
(d)
the balls have like charges, but do not carry equal charges.
(e)
neither ball is charged
Question 4:
An acetate rod is given a positive charge when it is rubbed with a cloth.
Use ideas about movement of charge to explain why this happens. Include a
diagram with your answer.
P4b: Uses of Electrostatics
Revision activity 1: use traffic lighting to highlight the areas that you need to revise and
then tick them off in the boxes once you have.
Learning objectives
Low Demand:
Standard Demand:
High Demand:
Recognise and describe how
static electricity can be useful:
★restarting a heart when it
has stopped (defibrillator);
★photocopier/laser
printers;
★removing dust from
smoke in chimneys;
★paint spraying.
Describe how static electricity
can be useful for restarting the
heart when it has stopped
(defibrillator):
★paddles charged;
★ good electrical contact
with patient’s chest
★ charge passed through
patient to make heart
contract;
★care taken not to shock
operator.
Explain how static electricity
can be useful in restating the
heart when it has stopped
(defibrillator):
★ paddles charged;
★ good electrical contact
with patient’s chest
★ charge passed through
patient to make heart
contract;
★care taken not to shock
operator.
Describe how static electricity
can be useful for electrostatic
dust precipitators to remove
smoke particles etc from
chimneys:
★metal plates/grids put
into chimneys;
★connected to a high pd;
★dust particles attracted to
plate/grid
★dust particles are
attracted together to form
larger particles;
★dust falls back down
chimney when particles
are heavy enough.
Explain how static electricity
can be useful in electrostatic dust
precipitators to remove smoke
particles etc from chimneys:
★metal plates/grids put
into chimneys;
★connected to a high pd;
★dust particles attracted to
plate/grid
★dust particles are
attracted together to form
larger particles;
★dust falls back down
chimney when particles
are heavy enough.
Describe how static electricity
can be useful for paint spraying:
★ spray gun charges;
★ paint particles charged;
★ repel giving fine spray;
★ object charged
oppositely to paint;
★ attracts paint;
★ even coat, less waste,
shadows painted.
Explain how static electricity
can be useful for paint spraying:
★ spray gun charges;
★ paint particles charged;
★ repel giving fine spray;
★ object charged
oppositely to paint;
★ attracts paint;
★ even coat, less waste,
shadows painted.
Revision activity 2: Make a poster or revision card about each use of electrostatics and
LEARN!
Question 1:
The diagram below shows an electrostatic smoke precipitator.
!
clean gas
end-on view of wires
dirty gas
soot particles
(a) The wires carry a negative charge. What happens as the smoke passes near the wire?
(b) Why is the plate given a positive charge?
(c) Describe the purpose of a smoke precipitator?
Question 2:
Static electricity can be used in the spray painting of car bodies.
!
(a)On the diagram show the charges on the spray-paint drops and on the car body.
(b)Carefully explain the process.
(c)Why should this spray painting be carried out in a dust-free atmosphere?
P4c: Safe Electricals
Learning objectives
Low Demand:
Recognise that a complete
loop is required for a circuit to
work.
State that an earthed
conductor cannot become live.
Low Demand:
Describe and recognise how
resistors can be used to change
the current in the circuit.
Standard Demand:
Explain the behaviour of simple
circuits in terms of the flow of
electric charge.
Standard Demand:
Describe how variable resistors
can be used to change the
current in a circuit.
★rheostat configured as a
variable resistor only.
Describe the relationships
between current, potential
difference and resistance.
★for a given resistor,
current increases as pd
increases and vice versa;
★for a fixed pd, current
decreases as resistance
increases and vice versa
State and use the equation:
★ resistance = voltage ÷
current
Low Demand:
Standard Demand:
State the colour coding for live,
neutral and earth wires:
★ live - brown
★ neutral - blue
★ earth - green
Describe that an earthed
conductor cannot become live.
Describe and explain the
functions of the live, neutral and
earth wires:
★ live - carried the high
voltage;
★ neutral - the second wire
to complete the circuit;
★ earth - a safety wire to
stop the appliance
becoming live
High Demand:
State and use the equation:
★resistance = voltage ÷
current
(A change of subject will be
required)
Low Demand:
Describe the reasons for the
use of fuses and circuit breakers
(as resettable fuses)
Low Demand:
Describe and recognise that
“double insulated” appliances do
not need earthing.
Standard Demand:
High Demand:
Describe how a wire fuse
works:
★ if the current becomes
too large;
★wire fuse melts, breaking
the circuit.
Explain how a wire fuse
reduces the risk of fire if the
appliance develops a fault.
★too large a current
causes the fuse to melt;
★preventing flow of
current;
★prevents flex overheating
causing fire;
★prevents further damage
to appliance.
Explain the reasons for the use
of fuses/circuit breakers as
resettable fuses (structure and
mode of operation not required)
Explain how a wire fuse and
earthing protects people.
Standard Demand:
Explain why “double insulated”
appliances do not need earthing:
★ case of appliance is a
non conductor and cannot
become live.
Draw below a diagram of a plug, use colour and add descriptions of what each of the wires do.
Exam Style Question
(a)Teresa set up the circuit shown in the diagram. The ammeter reading was 0.4 A.
!
"!
#!!!
$!!!
(i) State the value of the current through the 4 resistor?
[1]
(ii) State the value of the current through the 6 resistor?
[1]
(b) Calculate:
(i) the potential difference across the 6 resistor.
[2]
(ii) the potential difference across the 4 resistor.
[1]
(c)A third resistor is placed in series with the 4 and 6 resistors. The total resistance of 3
resistors in series is given by: Rtotal = R1 + R2 + R3. The current now falls to 0.25 A.
Calculate the value of the third resistor.
[3]
TOTAL / 8
Exam Style Questions
A piece of electrical equipment is designed to run on mains voltage.
It has a metal case.
Two safety measures are built into its design.
For each of the safety measures listed below explain why it is necessary and outline how it
works.
(a)the case of the piece of equipment is earthed
[3]
(b)a fuse is put into the circuit
[3]
TOTAL / 6
Further Questions:
What does it mean for an electrical appliance to be “double insulated”?
What is a “circuit breaker”?
P4d: Ultrasound
Revision Activity 1: use traffic lighting to highlight the areas that you need to revise and
then tick them off in the boxes once you have.
Learning objectives
Standard Demand:
Low Demand:
State and recgonise that
ultrasound is a longitudinal wave.
Recognise features of a
longitudinal wave:
★amplitude
★wavelength
★frequency
★compression
★rarefaction
Describe the features of a
longitudinal wave:
★amplitude
★wavelength
★frequency
★compression
★rarefaction
Standard Demand:
Low Demand:
Describe and recognise that
ultrasound can be used in
medicine:
★to look inside people by
scanning the body;
★to break down kidney
and other stones;
★to measure the speed of
blood flow in the body
Describe the applications of
ultrasound:
★body scans;
★breaking down kidney
and other stones
High Demand:
Describe the motion of
particles in longitudinal and
transverse waves.
High Demand:
Explain how ultrasound is used
in:
★ body scans (reflections
from different layers);
★breaking down
accumulations in the body
such as kidney stones.
Explain the reasons for using
ultrasound rather than X-rays:
★ able to produce images
of soft tissue;
★ does not damage living
cells
Which of the following pictures is of a transverse wave? Which is a longitudinal wave?
...................................................................
How can you tell? What makes the difference?
...................................................................
Revision Technique: Ensure you know the meanings of key words:
Key Word
amplitude
wavelength
frequency
compression
rarefactions
ultrasound
Label the amplitude and wavelength on this diagram:
Give three uses of ultrasound:
1.
2.
3.
Definition
Exam Style Questions
The diagram below shows a wave with various measurements taken along the wave.
!
50m
5m
10m
100m
(a)(i) What is the amplitude of the wave?
[1]
(ii) What is the wavelength of the wave?
[1]
(b)The diagram below shows a wave traveling along the slinky spring.
!
(i) Use a ruler to measure the wavelength of this wave.
[1]
(ii) Describe how the wave shown is similar to a sound wave traveling through air.
[2]
(c)Describe how the slinky spring can be made to show how light waves can travels.
[1]
(d) The diagram shows the shape of the wave produced on an oscilloscope (an instrument used for
analysing sounds). The wave on the screen has a frequency of 400Hz.
!i. On the diagram draw what you would see if the same note was played quieter. Label the line Q.
ii. On the diagram draw what you would expect to see if the musician played a note with a frequency
of 800Hz. Label the line F.
P4e: Treatment
Learning objectives
Low Demand:
Recall that nuclear radiation is
used in medicine.
Recall that x-rays and gamma
rays are electromagnetic waves.
Low Demand:
Recall that nuclear radiation
can damage cells.
Recognise that gamma rays
are used to treat cancer.
Recall that nuclear radiation is
used to sterilize hospital
equipment.
Recall that the person in
hospitals who takes x-rays and
uses radiation is a radiographer.
Standard Demand:
Recall that only beta and
gamma radiation can pass
through skin.
Standard Demand:
Describe that beta or gamma
emitters are used as tracers in
the body.
Standard Demand:
Describe that X-rays and
gamma rays:
★have similar
wavelengths;
★are produced in different
ways.
High Demand:
Explain that:
★ gamma rays are given
out from the nucleus of
certain radioactive
materials;
★X-rays are made by firing
high speed electrons at
metal targets
★X-rays are easier to
control than gamma rays
High Demand:
Explain how radioactive
sources are used in medicine:
1. to treat cancer
★gamma rays focused on
tumour;
★wide beam used;
★rotated round patient
with tumour at the centre;
★limiting damage to noncancerous tissue.
2. as a tracer
★beta or gamma emitter;
★drunk/eaten/ingested/
injected into body;
★allowed to spread
through the body;
★followed on the outside
by a radiation detector.
Draw diagrams to show how these two types of waves are produced.
X-rays
Gamma Rays
Draw diagrams to explain how gamma rays can be used to treat cancer.
P4f: Radioactivity
Learning objectives
Low Demand:
Standard Demand:
High Demand:
Describe and recognise that
the radioactivity of an objective is
measured by the number of
nuclear decays emitted per
second.
Describe and recognise that
radioactivity decreases with time.
Describe radioactivity
substances as decaying naturally
and giving out nuclear radiation
in the form of alpha, beta and
gamma.
Describe radioactivity as
coming from the nucleus of an
atom that is unstable.
State that an alpha particle is a
helium nucleus.
State that a beta particle is a
fast moving electron.
Explain and use the concept of
half-life.
Interpret graphical or numerical
data of radioactive decay.
Low Demand:
Describe that radiation comes
from the nucleus.
High Demand:
Describe what happens to a
nucleus when an alpha particle is
emitted.
★mass number decreases
by 4;
★nuclear has two less
neutrons;
★nucleus has two less
protons;
★atomic number
decreases by 2;
★new element formed.
Describe what happens to a
nucleus when a beta particle is
emitted:
★mass number is
unchanged
★nucleus has one less
neutron;
★nucleus has one more
proton;
★atomic number increases
by one.
Construct and balance simple
equations in terms of mass
numbers and atomic numbers to
represent alpha and beta decay.
1 Complete the table.
isotope
14
number of
protons
mass number
number of
neutrons
6C
226
88Ra
209
81Tl
235
92U
2 Complete the following nuclear equations.
232
14
90Th
6C
2He
+
Ra
0
–1e
+
N
216
84Po
+
212
82Pb
241
94Pu
+
241
95Am
+
221
87Fr
Ac
3
4
238
4
2He
92U
decays by emitting an alpha particle and two beta particles. Write down the
nuclear equations for each decay. Use X, Y or Z if you do not know the symbol for an
element. Which element is finally produced?
The final element is
.
4 Explain what effect losing a gamma ray has on a nucleus.
______________________________________________________________________
_____________________________________________________________________
5 A beta particle is an electron. There are no electrons in the nucleus of an atom. What
happens to
a nucleus when a beta particle is emitted?
______________________________________________________________________
______________________________________________________________________
______________________________________________________________________
Create a mindmap about radioactivity.
what it is
what causes it
Background Radioactivity
Tracers
Radioactivity
dating rocks
smoke detectors
dating once living materials
Exam-Style Questions
Question 1:
The chart below shows the change in mass number and atomic number of an atom for
different types of radioactive decay.
change in atomic number
change in mass number
A
-1
0
B
-2
-4
C
0
0
D
+1
0
(a)Write down the letter which shows how the mass number and atomic number change for
the following:
(i) emission of an alpha particle
[1]
(ii) emission of a beta particle
[1]
(iii) emission of gamma radiation
[1]
Question 2:
(a)Most of the carbon in your body is carbon-12
12
6C.
Draw a diagram of this atom.
(b)Another isotope is carbon-14 146C with a half-life of 5700 years.
i.What are the atomic number and mass number of this isotope?
ii.Explain the words in italic.
iii.What fraction of 146C remains after 11400 years?
Question 3: Cloze Activity
atoms
decreases
nucleus
alpha
gamma
radioactivity
beta
half
short
decay
long
time
zero
The ............... of a sample always ............... over time. Each time a decay
happens ............... , ............... or ............... radiation is emitted. This means a
radioactive ............... had decayed. The problem with trying to measure the time for
all the atoms to decay is that the activity never reaches ............... .
The half-life is the ............... taken for ............... of the radioactive ............... now
present to ............... . An isotope with a ............... half-life decays more quickly than
an isotope with a ............... half life.
A radioactive substance is one with unstable nuclei which decay by emitting
radiation. The activity of a radioactive substance is measured in Becquerels (Bq).
1. If a substance had an activity of 5Bq, how many of its nuclei will decay every
second?
2. An activity of 2Bq is equivalent to how many counts per minute? (A count is one
nucleus decaying).
3. What happens to the activity of a radioactive isotope over a period of time?
4. Explain why this happens.
Radioactive substances are dangerous if their radioactivity is above a certain level
– so it’s important to know how long it takes for a substance’s radioactivity to fall
to a safe level.
1. What is the half-life of a radioactive substance?
2. Will the activity of a radioactive substance ever reach zero?
3. A sample of U-238 has an activity of 1160 counts per minute. Six hours later, its
activity has fallen to 145 counts per minute. What is the half-life of the sample?
4. The waste produced by nuclear power plants has a long half-life. Why does this
make the waste difficult to dispose of in a safe way?
Work out the half-life of a radioactive isotope that...
1. Starts with an activity of 20Bq and four minutes later has a radioactivity of 5Bq.
2. Starts with an activity of 16,384Bq and 42 minutes later has an activity of 2Bq.
3. Starts with an activity of 800Bq and nine million years later has an activity of 100Bq.
4. Starts with an activity of 64Bq and 6 seconds later has an activity of 4Bq.
P4g: Uses of Radioisotopes
Learning objectives
Low Demand:
Standard Demand:
High Demand:
Describe and recognise that there
is the background radiation in the
environment which is always present.
Describe background radiation and
state that it is caused by radioactive
substances in rocks and soil and by
cosmic rays.
Explain that some background
radiation comes from waste products
and man made sources eg waste
from
★industry
★hospitals
Low Demand:
Standard Demand:
High Demand:
State that radioisotopes are used
as tracers in industry and hospitals.
Low Demand:
Describe that alpha sources are
used in some smoke detectors.
Recall examples of the use of
tracers:
★to track dispersal of waste;
★to find leaks/blockages in
underground pipes;
★to find the route of
underground pipes.
Describe how tracers are used in
industry:
★radioactive material put into
the pipe;
★gamma source used so that
it can penetrate the surface;
★progress tracked with
detector above ground;
★leak/blockage shown by
reduction/no radioactivity after
this point.
Standard Demand:
Describe how a smoke detector
with an alpha source works
Standard Demand:
Recall that radioactivity can be
used to date rocks.
Recall that measurements from
radioactive carbon can be used to
find the date of old materials.
High Demand:
Explain how the radioactive dating
of rocks depends on the calculation
of the uranium/lead ratio.
Explain how measurements of the
activity of radioactive carbon can
lead to an approximate age for
different materials:
★the amount of Carbon 14 in
the air has not changed for
thousands of years;
★when an object does (e.g.
wood) gaseous exchange
with the air stops;
★as the Carbon 14 in the
wood decays the activity of
the sample decreases;
★the ratio of the current
activity from living matter to
the activity of the sample
leads to a reasonably
accurate date.
P4h: Fission
Learning objectives
Standard Demand:
Low Demand:
Recognise that nuclear power
stations use uranium as a fuel.
Describe the main stages in
the production of electricity
★ source of energy;
★used to produce steam;
★used to produce
electricity.
Describe how domestic
electricity is generated at a
nuclear power station:
★nuclear reaction;
★producing heat;
★producing steam;
★turning a turbine;
★turning a generator.
Standard Demand:
Low Demand:
Describe that the decay of
uranium can be a chain reaction.
Describe that a nuclear bomb
is a chain reaction that has gone
out of control.
Describe the process that
gives out energy in a nuclear
reactor as nuclear fission.
State that nuclear fission
produces radioactive waste.
Describe how materials
become radioactive when they
absorb extra neutrons.
High Demand:
Describe what happens to
allow Uranium to release energy:
★uranium nucleus hit by
neutron;
★causes nucleus to split;
★energy released.
High Demand:
Explain what it meant by a
chain reaction:
★when each uranium
nucleus splits more than
one neutron is given out;
★these neutrons can
cause further uranium
nuclei to split.
Explain how scientists stop
nuclear reactions going out of
control:
★rods placed in the
reactor
★to absorb some of the
neutrons;
★allowing enough
neutrons to remain to keep
the process operating.
Look at the nuclear equation for nuclear fission below and then answer the questions that
follow.
235 U
92
+ 10n
90
36Kr
+ 14356Ba + 3(10n) + -rays + energy
1
How many protons are there in the uranium nucleus?
___________________________________________________________________
How many neutrons are there in the uranium nucleus?
___________________________________________________________________
How many protons are there in the nuclei on the right-hand side of the equation?
___________________________________________________________________
How many neutrons are there on each side of the equation?
___________________________________________________________________
Uranium-235 is radioactive. Why is a neutron needed to start the fission process?
___________________________________________________________________
___________________________________________________________________
What makes this reaction so useful in producing a lot of energy?
___________________________________________________________________
2 A typical nuclear power station generates about 800 MW of electrical power. 1 kg of
uranium releases approximately 2 x 1013 J of energy. A power station has an efficiency
of about 30%.
How many joules of electrical energy are generated in a year?
___________________________________________________________________
___________________________________________________________________
Calculate how much energy must be produced by the uranium to provide this
electrical energy.
___________________________________________________________________
___________________________________________________________________
Calculate the mass of uranium required by the power station in 1 year.
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
Comment on your answer.
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________