how is speed calculated and what are the standard units? 3 marks stimulating challenging innovative...
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How is speed calculated and what are the standard units?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
How is speed calculated and what are the standard units?
- Distance- Divided by time- m/s
How is acceleration calculated and what are the standard units?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
How is acceleration calculated and what are the standard units?
- Change in velocity - Divided by time taken- m/s2
What is the difference between speed and velocity?
2 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What is the difference between speed and velocity?
- Speed is how fast you are going. - Velocity is how fast you are going in
a particular direction
What can be shown on a distance time graph?
5 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What can be shown on a distance time graph?
- Gradient = speed (distance/time)- Flat section = stationary (not change
in distance)- Steeper gradient = faster- Downhill sections = going back to
starting position- Curves = acceleration
What can be shown on a velocity-time graph?
7 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What can be shown on a velocity-time graph?
- Gradient = acceleration- Flat sections = steady speed- Steeper = greater acceleration- Uphill = acceleration- Downhill = deceleration- Area under graph = distance
travelled - Curve – changing acceleration
What is the difference between mass and weight?
4 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What is the difference between mass and weight?
- Mass is the amount of stuff an object is made of.
- Mass is measured in kilograms (Kg)- Weight is caused by the pull of
gravity.- Weight is measured in Newtons (N)
How are mass and weight related and what are the units?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
How are mass and weight related?
- Weight = mass x gravitational field strength
- Weight – Newtons (N), Mass – Kilograms (kg)
- Gravitational field strength = N/Kg
How do balanced forces affect the motion of an object?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
How do balanced forces affect the motion of an object?
- No change in velocity- Stationary objects remain stationary- Objects that are moving, remain at
constant speed.
How do unbalanced forces affect the motion of an object?
2 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
How do unbalanced forces affect the motion of an object?
- Causes acceleration - Or deceleration
What affects the size of a resultant force?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What affects the size of a resultant force?
- Force = mass- X- Acceleration
Or (F = ma)
What is meant by terminal velocity?
5 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What is meant by terminal velocity?
- Objects in free-fall- Initially accelerate- Resistance slows them down- Until reach a constant maximum
speed- Where resistance forces =
accelerating forces.
What affects the stopping distance of a car and how is it calculated?
9 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What affects the stopping distance of a car and how is it calculated?
- Thinking distance is affected by- speed and- How dopey you are
- Braking distance is affected by - Wear and tear of brakes and tyres- Weather- Condition of road- How heavy the vehicle is- How fast the vehicle is travelling
What is work done and how is it calculated?
4 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What is work done and how is it calculated?
- Work is energy transferred- Work is the force need to move an
object a distance- Calculated by work done = force x
distance- Work is energy transferred and so
units are Joules.
What is weight and how is it calculated?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What is weight and how is it calculated?
- Weight = mass x gravitational field strength
- The force by which the mass of the object is pulled down to earth
- Measured in Newtons (N)
What are the difference and similarities between kinetic and potential energy?
7 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What are the difference and similarities between kinetic and potential energy?
- Both are forms of energy- Kinetic is movement energy- Kinetic energy = ½ x mass x velocity2
- Potential is a store of energy- Potential energy can be elastic
potential or - Gravitational potential energy- Both are measured in joules (J)
How do you calculate momentum and what are the units?
4 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
How do you calculate momentum and what are the units?
- Mass x velocity- Kg m/s- Momentum before = momentum
after- Momentum is conserved when no
external forces act.
How do you calculate the force acting on an object that causes a change in momentum?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
How do you calculate the force acting on an object that causes a change in momentum?
- Force (N) = change in momentum (kg m/s)time taken for change (s)
How do crumple zones help to reduce the impact on a person?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
How do crumple zones help to reduce the impact on a person?
- They increase the time taken for the car to stop.
- The longer it takes for a change in momentum
- The smaller the force on the person.
What can help to reduce the impact on a person in a car crash?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What can help to reduce the impact on a person in a car crash?
- Crumple zones- Seat belts- Air bags
What is gravitational potential energy and how is it calculated?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What is gravitational potential energy and how is it calculated?
The energy stored in an object because if its position above the Earth
Energy = mass x gravitational field strength x height
Energy – Joules (J)Mass – Kilograms (kg)Gravitational field = N/kgHeight = metres (m)
What is kinetic energy and how is it calculated?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What is kinetic energy and how is it calculated?
Another name for movement energy
Energy = 0.5 x mass x velocity x velocity
Mass – Kilograms (kg)Velocity = metres per second, (m/s)Energy = Joules (J)
What causes static electricity?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What causes static electricity?
- Rubbing materials together- Causes electrons- To move from one material to
another- The material which loses electrons
becomes positively charged. - The material that gains electrons
becomes negatively charged.
Why does a van de graff generate a spark?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
Why does a van de graff generate a spark?
- Electrons build up on the dome- As more electrons build up, the
potential difference increases. - When the potential difference is big
enough, a spark can be produced.
Where is static electricity helpful?
2 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
Where is static electricity helpful?
- In smoke precipitators on chimneys which attract dust particles.
- In photocopiers
Where is static electricity a problem?
2 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
Where is static electricity a problem?
- Lightening - Petrol pump at petrol station – could
cause an explosion.
What is meant by current?
2 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What is meant by current?
- The flow of electrons - Measure in amps
What is meant by voltage?
2 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What is meant by voltage?
- The driving force that pushes current round.
- Measured in volts
What is meant by resistance?
2 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What is meant by resistance?
- Anything that slows down the flow of current
- Measured in ohms, Ω
What happens when you increase voltage?
1 mark
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What happens when you increase voltage?
- More current will flow
How is an ammeter used and what does it show?
4 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
How is an ammeter used and what does it show?
- Measures the current- In amps - Must be placed in series - Can be placed anywhere in the
circuit
How is an voltmeter used and what does it show?
4 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
How is an voltmeter used and what does it show?
- Measures the voltage - In volts- Must be placed in parallel- Must be placed across a component
(proper name is potential difference)
What does a voltage-current graph look like for a resistor, at constant temperature, and why?
4 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What does a voltage-current graph look like for a resistor, at constant temperature, and why?
High Temp
Low Temp
Cur
rent
Potential Difference
• Straight line – therefore directly proportional, so an ohmic resistor at constant temperature.
• Resistance decreases as temperature increases
What does a voltage-current graph look like for a filament lamp and why?
6 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What does a voltage-current graph look like for a filament lamp and why?
• Curve – therefore not directly proportional, so not an ohmic resistor.
• Resistance increases as current increases
• Caused by increase in temperature as current increases.
• Increase in temperature causes particles to move more in the wire.
• Reversing the current has not effect – they are a mirror image.
What does a voltage-current graph look like for a diode and why?
4 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What does a voltage-current graph look like for a diode and why?
• Only works in ONE direction
• No a straight line – so not an ohmic conductor.
• Reverse direction, the current is negliable.
What are the circuit symbols for:
- Cell- Battery- Switch- Filament lamp- Fuse- Fixed resistor
- Variable resistor- Dioide- Thermistor
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What are the circuit symbols for:Cell – push electrons around the circuit
Battery – consists of 2 or more cells Switch – enables
current to be switched on or off
Lamp – emits light
Diode – only allows current in ONE DIRECTION ONLY.
Fixed resistor – limits current flowing in a circuit
Variable resistor – varies current flowing in a circuit
Fuse – a wire that melt when current is TOO high.
Thermistor – reacts to changes in temperature
What does a voltage-current graph look like for a thermistor and why?
4 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
Thermistor
High Temp
Low Temp
Cur
rent
Potential Difference
• Straight line – therefore directly proportional, so an ohmic resistor at constant temperature.
• Resistance decreases as temperature increases
What does a voltage-current graph look like for a thermistor and why?
What are the key features of a series circuit?
4 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What are the key features of a series circuit?
- Current only has one route to flow- Current is the same at all locations- Potential difference is shared
between components- Resistance is calculated by adding all
of the resistances for the components together.
What are the key features of a parallel circuit?
4 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What are the key features of a parallel circuit?
- Current only more than one route to flow
- Current shared between the different branches
- Potential difference is the same across all components
- Resistance depends on the components resistance.
Give an example of a series circuit and a parallel circuit.
2 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
Give an example of a series circuit and a parallel circuit.
- Series = torch, Christmas fairy lights- Parallel = components in a car (fan,
lights, wipers etc).
What is the difference between a.c. and d.c. and where are they used?
7 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What is the difference between a.c. and d.c. and where are they used?
a.c. - Alternating current- The current switches direction - Used in mains electricity - Mains is set at 50Hz
d.c.- Direct current- Current flows in one direction only- Used by batteries
What wires are found in a plug and how are they connected?
6 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What wires are found in a plug and how are they connected?
- yellow/green- Earth
- Brown - Live
- Blue- Neutral
How do fuses work?
5 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
How do fuses work?
- Fuses are pieces of wire- When current is too high, the wires
melt- As the wires get hotter as current
increases.- The thicker the wire the more current
it can withstand without melting. - Prevent surges of electricity
How does earthing work?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
How does earthing work?
- If a fault develops where a live wire touches the metal case
- the large current - Flows through the earth wire
How is the power rating on an electrical item calculated?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
How is the power rating on an electrical item calculated?
Power = Voltage x Current
Or
Power = Energy/Time
What is meant by charge and how is it calculated?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What is meant by charge and how is it calculated?
- Current is the flow of electrical charge (in Coulombs, C) around a circuit.
- When current flows for a length of time then charge (Q) can be calculated:
- Charge = Current x Time
How is the energy transferred in a circuit calculated?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
How is the energy transferred in a circuit calculated?
Energy transferred = Charge x potential difference
What did Rutherford find out?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What did Rutherford find out?
- He came up with the nuclear model of the atom.
- In the centre is a nucleus- Where mass is concentrated- Made up of protons and neutrons- Around the outside is empty space- With electrons whizzing around- Electrons have a negligible mass.
What is meant by an isotope?
2 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What is meant by an isotope?
- An element with the same number of protons
- But a different number of neutrons
What are the three radioactive decay methods and what is the difference between them?
14 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What are the three radioactive decay methods and what is the difference between them?
- Alpha- Is a helium nuclei (mass of 4, charge +2)- Heavy, does not travel far (low penetration)- Strongly ionising – knock electrons off other atoms when collide.
- Beta- Is an electron (no mass, charge 1-)- Quite fast moving - Small- Moderately penetrating, - Moderately ionising
- Gamma- Is a photon (no mass, no charge)- Penetrate a long way- Weakly ionising – pass through rather than collide with atoms.
What is the difference between nuclear fission and fusion?
11 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What is the difference between nuclear fission and fusion?
Fusion- The fusing (joining) of small nuclei- Form a larger nuclei- Releases a lot of energy (happens in stars)- Only happens at extremely high temperatures- Contained in a magnetic field as materials would just vaporise under
high heat.
Fission- Splitting heavy nuclei in to smaller ones- Used in nuclear power stations and submarines- Heat used to heat water to drive turbine- Fuel is uranium and plutonium - Results in radioactive waste- Causes a chain reaction
What are the stages of nuclear fission?
8 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What are the stages of nuclear fission?
Fission – the splitting of the atomUsing a neutronWhich collides with an atom and causes it to split. On splitting, the atom releases two more neutrons which collide with other atoms and cause them to split too. This causes a chain reaction. Releasing lots of energy. This is how the atomic bomb works. The fuel is usually enriched uranium
What does a nuclear reactor need to control the reaction?
8 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What does a nuclear reactor need to control the reaction?
- Control rods – absorb surplus neutrons
- Coolant – to transfer heat from the reaction to the heat exchanger
- Thick steel walls to withstand the high temperatures
- Thick concrete to stop the radioactivity escaping
What happens in nuclear fusion?
9 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What happens in nuclear fusion?
- The joining of nuclei- E.g. hydrogen- 2 Protons collide, producing heavy hydrogen- 2 more protons collide, producing- Heavier nuclei- Two heavier nuclei collide to produce - e.g. helium - Happens in the Sun (contains a core of
plasma where atoms have no electrons)- Releases massive amounts of energy
How has the model of the atom changed?
5 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
How has the model of the atom changed?
Plum pudding model:- All the charged particles are randomly spread
throughout the atom – like raisins in a sponge pudding.
New Model:- Nucleus contains protons and neutrons- Nucleus contains most of the mass of the atom.- Electrons are found in shells around the nucleus- Electrons are held in place by electrostatic
charges.
What do the two numbers with an element tell you?
5 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What do the two numbers with an element tell you?
Mass Number (the bigger number)The total number of protons AND neutrons.
Atomic Number (the smaller number)The number of protons in the atomIn an uncharged atom, also the number of electrons.
What is Half Life?
2 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What is Half Life?
The time taken for a radioactive COUNT RATE to decrease by HALF.
Or
The time taken for the number of radioactive nuclei to halve.
What affects Half Life?
2 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What affects Half Life?
Nothing
It is a completely RANDOM event.
How is the penetration of each type of radioactivity different?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
How is the penetration of each type of radioactivity different?
Alpha – Low as stopped by air/paper
Beta – Medium as stopped by metal
Gamma – High – stopped only by thick lead or concrete.
How can the type of radioactivity be shown using an electric field?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
How can the type of radioactivity be shown using an electric field?
If pass through an electric field:Alpha – As positively charged (Helium Nuclei), it is attracted towards the negative terminal.
Beta – As negatively charged (electron) it is attracted towards the positive electrode)
Gamma – As it is uncharged and has no mass it is unaffected and so passes through without any change.
How can the type of radioactivity be shown using an magnetic field?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
How can the type of radioactivity be shown using an magnetic field?
If pass through an electric field:Alpha – Deflected slightly. As it has a greater mass than Beta, it isn't deflected as much.
Beta – Deflected in the opposite direction to Alpha and by more as it is lighter.
Gamma – Passes through without any change.
Why is ionisation dangerous?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
Why is ionisation dangerous?
As radioactivity pass through, it can knock electrons off of atoms – causing ions to be produced.
X-rays cause ionisation and can damage and kill cells.
Alpha is the most dangerous inside the body as it has a greater ionising effect.
Where is radioactivity useful?
5 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
Where is radioactivity useful?
Automatic thickness monitoring of paper, metals etc in a factory.
Radioactive tracers – for medical use.
Carbon Dating
Uranium Dating
Smoke Alarms
How does a Star Form?
9 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
How does a Star Form?• Star are formed from clouds of dust and gas.• Gravity pulls the clouds so they come spiralling inwards. • The gravitational energy is converted into thermal (heat) energy and
therefore the temperature rises. • As the temperature rises, hydrogen nuclei undergo nuclear fusion. • They form helium nuclei.• They now give out massive amounts of heat and light – they a now a
new star. • Heat continues to be created by nuclear fusion. • This provides an outward pressure which balances the pull of gravity.• This is the stable period – known as main sequence star.
What is a red giant, white dwarf and black dwarf?
4 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What is a red giant, white dwarf and black dwarf?
• The star will swell up into a red giant • One way to remember it is like a spot – getting bigger. • A small star (our Sun) will then cool and contract into a white dwarf. • As the light then fades it will become a black dwarf.
How does a Supernova occur?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
How does a Supernova occur?
• Big stars, however, start to glow brightly again and they undergo more nuclear fusion.
• They expand and contract several times forming heavier elements in various nuclear reactions.
• Eventually they explode in a supernova.
How does a Supernova lead to a black hole?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
How does a Supernova lead to a black hole?
• The exploding supernova throws out layers of dust and gas.• Leaves a very dense neutron star.• If the star is big enough – it is a black hole.
Where can you find gravity stronger than on Earth?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
Where can you find gravity stronger than on Earth?
• The matter from a neutron star and white dwarfs and black holes are made is millions of times denser than any matter on Earth because the gravity is so strong it even crushes the atoms.
What evidence is there that we were created from old stars?
3 marks
Stimulating Challenging Innovative Exciting Nurturing Creative EngagingJohn O’Gaunt Science Team 2013 (Produced by Mr P Scutt)
What evidence is there that we were created from old stars?
• The dust and gas thrown off will form into second generation stars like our Sun.
• The heavier elements in our Sun and the inner planets gives our evidence that we were created from an old stars dying sneeze.