Triple Science Physics P1, P2 and P3. Core Questions and Keywords and Definitions

Transcription

1 Triple Science Physics P1, P2 and P3 Core Questions and Keywords and Definitions

2 Describe how to measure the focal length of the lens. Explain what the eyepiece lens does. Describe the image the student sees when he looks through the lens. A ray of light changes direction when it enters a converging lens, what is this called? How does the eyepiece on a simple telescope work? What do waves transfer? What is the difference between a real and a virtual image? What changes when light enters a denser material? What is the difference between the geocentric and the heliocentric models of the universe? P1 Core Questions First you measure the distance / length (1) from the lens to image / screen / focal point (1) An eyepiece lens magnifies the image (1). An eyepiece lens also refracts the light (1) When looking through an eyepiece lens you would see a magnified (1), erect (1) and virtual (1) image of the object Refraction The eyepiece lens is a small converging lens that is used to magnify the image produced by the larger converging lens at the other end of the telescope. Energy and information but not matter A real image is when the rays of light are bought together by a lens and the image is observed on a screen, whereas a virtual image is when the image is observed on a surface like a mirror. The speed and direction of the light ray The geocentric model has the earth at the centre of the solar system and everything else orbiting around it. Whereas the heliocentric has the sun at the centre and the planets orbiting around it. Galileo observed 4 moons (1) orbiting Jupiter (1) and not Earth, therefore not everything orbits the Earth (1) Energy and information Explain how Galileo's observations supported the heliocentric model of the solar system What do light waves transfer? State an example of a longitudinal wave. P-wave, ultrasound, infrasound, sound, P waves (each worth 1) Give examples of transverse waves All of the electromagnetic waves including light etc. and seismic S (secondary) waves. Describe what happens to particles in longitudinal waves The direction of the vibration is the same as the direction of energy travel Describe what happens to particles in transverse waves The direction of the vibration is perpendicular/at a right angle to the direction of energy travel Describe the motion of particles in a material when this When a P waves occur, the particles vibrate/oscillate (1) in the ultrasound wave passes through. same direction as/parallel to the direction of the wave travels What is the frequency of a wave and what is it measured in? What is the wavelength and what is it measured in? What is the amplitude and what is it measured in? (1) The number of waves in 1 second and the unit is Hertz (Hz) The length of 1 complete wave cycle. It is measured in meters (m). The distance from the centre of a wave to the top of the wave. It is measured in meters (m). Which scientist discovered infra-red radiation? Which scientist discovered ultra-violet radiation? What are the colours of light in the visible spectrum? (Start with the longest wavelength) What is the order of waves in the electromagnetic spectrum? (Start with the longest wavelength) Are the electromagnetic waves transverse or longitudinal Which travels faster in a vacuum light or radio waves? Which end of the electromagnetic spectrum has waves of the longest wavelength? Which end of the electromagnetic spectrum has waves of the highest frequency? P1 Topic 2 Core Questions William Herschel Johann Ritter Red, Orange, Yellow, Green, Blue, Indigo, Violet. Radio waves, Microwaves, Infrared waves, Visible light, Ultraviolet rays, X-rays, Gamma rays. Transverse Neither, all electromagnetic waves travel at the same speed in a vacuum. Radio waves Gamma rays

3 As the frequency of a wave increases, what happens to the potential danger? What are the harmful effects of excessive exposure to: 1. Microwaves 2. Infrared 3. Ultraviolet 4. X-rays and gamma rays? Name some of the uses of: 1. Radio waves 2. Microwaves 3. Infrared 4. Visible light 5. Ultraviolet 6. X-rays 7. Gamma rays Describe a harmful effect of ultraviolet waves. Which type of radiation in the electromagnetic spectrum is likely to be the most dangerous? Suggest other ways in which people can protect themselves from these ultraviolet waves. Describe one use of ultraviolet radiation. Which part of the electromagnetic spectrum has the highest frequency? X-rays have many uses. Describe one use for X-rays other than medical uses. It increases too because of the increased energy. 1. Internal heating of body cells 2. Skin burns 3. Damage to surface cells and eyes, leading to skin cancer and eye conditions 4. Mutation or damage to cells in the body 1. Broadcasting, communications and satellite transmissions. 2. Cooking, communications and satellite transmissions 3. Cooking, thermal imaging, short range communications, optical fibres, TV remote controls and security systems. 4. Vision, photography and illumination. 5. Security marking, fluorescent lamps, detecting forged bank notes, disinfecting water. 6. Observing the internal structure of objects, airport security scanners and medical X-rays. 7. Sterilising food and medical equipment and the detection of cancer and its treatment. 8. Dangers of UV radiation include damage to skin, sunburn, skin cancer, damage to eyes, eye problems, cataracts (Each worth 1 mark) This would be gamma rays/γ (1) They can wear sunscreen/suncream, sunglasses/uv glasses, go into shade/stay indoors, wear protective clothing (Each worth 1 mark) A use of UV radiation can be: security marking (1) where ink absorbs UV and reradiates (visible) light (1) fluorescent lamps (1) where coating absorbs UV and reradiates (visible) light (1) genuine bank notes (1) in which the watermark absorbs UV and reradiates (visible) light (1) disinfecting water (1) where the UV kills bacteria (1) sun beds (1) where UV absorbed by (melanin in) skin (1) Gamma rays (1) have the highest frequency A use of X-ray radiation can be: (at the) airport /customs / docks / security checks (1) for dangerous/illegal items (1) checking welds (1) to examine under the surface (1) checking paintings eq (1) to look for detail under the top paint layer (1) X-ray telescopes/astronomy (1) to study/look at objects in space (1) check packaging e.g. cans/packets (1) (to see if) filled to correct level (1) sterilising (1) food/hospital equipment (1) How many different colours are there in visible light? 7 What is the name of the ionising radiations is from a Gamma rays radioactive source and is also part of the electromagnetic spectrum? Infrared is used in an electric toaster. Infrared is also used by The wavelength/frequency of the infra-red radiation in the television remote control. toaster is of a higher frequency (1) Explain why using a television remote control does not burn anyone. In the electromagnetic spectrum, what radiation is between Microwaves radio waves and infra-red radiation?

4 Some users believed that sunglasses would protect their eyes from the X-rays. Explain how effective this would be as a precaution. Name the radiation that causes skin cancer Describe a use of gamma radiation. Microwaves can be used for satellite communications. State another use for microwaves. Name 3 types of ionising radiation that transfer energy? Where does ionising radiation come from? The result would not be not effective (1) because X-rays can easily penetrate sunglasses (1) UV radiation Any of the following: Sterilising food /medical equipment Detection / treatment of cancer imaging /detect flaws in materials Any of the following: Cooking Monitoring the weather / mobile phones Alpha particles, beta particles and gamma rays Radioactive sources continuously emit ionising radiation. What is the solar system and what is it part of? Put the following in order of size starting with the smallest. Sun, universe, moon, planet, galaxy, earth. What is the definition of a galaxy? Our Solar System is near the edge of a galaxy called the... Large telescopes which collect visible light to explore the Universe are usually placed near the tops of mountains. Suggest why radio telescopes do not have to be placed high up a mountain. Suggest why, when a galaxy has a very large red-shift, some of its visible light is not detected through the Earth s atmosphere. Name one type of radiation that can reach the surface of the Earth from stars. Name one type of radiation from stars that cannot be detected at the Earth's surface but can be detected using satellites. P1 Topic 3 Core Questions It is made up of the sun and the 8 planets that orbit it and it is part of the milky way galaxy. Moon, Planets (Earth), Sun, Galaxy, Universe. A cluster of stars Milky way Because radio waves are not absorbed by the atmosphere (1) Because light might be shifted into infrared region (1) and some infrared is absorbed by atmosphere (1) Any one of Radio waves visible light waves microwaves Any one of X-ray gamma ray far infrared Both radio (waves) (1) and microwaves (1) can be detected on the Earth s surface. Radio waves are not absorbed by the atmosphere Name one type of electromagnetic radiation that satellites on the Earth s surface can detect. Suggest why radio telescopes do not have to be placed high up a mountain. Some scientists look for signs of water on other planets. As water is needed for life, if water is found then it gives Suggest why they do this. possibility of life What methods are used to search for life beyond earth? Space probes orbit other planets like mars photographing the surface so Scientists can decide where water might have been. The scientists can then land Landers to do soil experiments and look for life in the most promising spots. SETI analyses radio waves from space for signals from extra-terrestrial life. What is a spectrometer? A device that can split up the different wavelengths of light. (It splits light into its different colours). State what a nebula is (cloud of) dust and/or gases (1) A nebula is a cloud of gas and dust where stars are formed. The gas and dust is pulled together by gravity (1) which then A hot object forms when gas and dust in a nebula come converts gravitational/kinetic energy into thermal energy(1) together. Explain why the gas and dust come together and form a hot object. Describe how the mass of a main sequence star will affect what the star finally becomes. Stars with a similar or smaller mass of our sun will become a white/black dwarf (1)

5 Describe the life cycle of stars like our Sun What is the Big Bang theory? What is the Steady State theory? The Steady State Theory is not as widely accepted as the Big Bang Theory. Suggest a reason for this. How do we know that galaxies further way from us are moving faster than galaxies closer to us? CMB is an abbreviation for... Whereas a more massive will become a neutron star / black hole (1) Stage 1: Nebula - a cloud of dust and gases (mainly hydrogen) pulled together by gravity. Stage 2: Star (main sequence) - As the nebula grows the gravitational pull gets stronger and the pressure and the heat builds resulting in the formation of a star. Stage 3: Red giant - When most of the hydrogen has fused into helium the core collapses and the outer layers expand. Stage 4: White dwarf - The red dwarf throws off a shell of gas and what remains will be pulled together by gravity and collapses. No further reactions happen inside a white dwarf. The whole universe started out as a tiny point of concentrated energy about 13.5 billion years ago. Since the big bang the universe has been expanding ever since. The universe has always existed and has been continuously expanding with new matter being created as it expands. Because there is more evidence for the big bang theory (1), it is also more reliable as cosmic background radiation does not support Steady State theory (1) The faster a galaxy moves, the more red shift is seen. Observations show us that there is more red shift from more distant galaxies and so they must be moving faster. Cosmic microwave background radiation The frequency of ultrasound is Ultrasound is used for Explain why ultrasound rather than X-rays are used for foetal scanning. Describe what is meant by infrasound waves. Compared to normal sound waves, infrasound waves always have a smaller Name a use of infrasound Explain which is the best type of sound wave for whales to use when communicating over long distances Describe what happens at the plate boundary to cause an earthquake. Explain what causes the plates to move. The instrument used to detect earthquakes is a Earthquakes produce P-waves and S-waves. Describe what can happen to these waves when they reach the boundary between the crust and the mantle Waves from an earthquake are examples of Describe how particles in the ground move when P-waves pass through it. What can P-waves travel through? What can S-waves travel through? P1 Topic 4 Core Questions more than Hz Communication between animals, Sonar and foetal scanning Ultrasound is not dangerous (1) but X-rays are because they can damage to tissue/dna OR mutate cells (1) in the body. Infrasound waves are longitudinal waves (1) with a frequency less than 20 Hz (1) frequency Communication between animals, detection of animal movement in remote places, detection of volcanic eruptions and meteors Infrasound (1) is the best type of sound for whales communicating because it decreases in amplitude is least (1) and can be detected/'heard' further away (1) An earthquake occurs when a plate moves/slip (1) causing a sudden release of energy (1) Plates move due to heat from the Earth s core (1) which causes convection currents (1) in the mantle (1) Seismometer When P-waves or S-waves meet the boundary between the crust and mantle, they can be reflected (1) and refracted (1) both transverse and longitudinal waves Particles in P-waves vibrate (1) in same direction as wave/energy moves (1) P-waves can travel through solid and liquid at speeds of about 10km/s. So these waves can travel from one side of earth through to the opposite point. S-waves can travel through solids but NOT liquids at speeds of about 6km/s. So these waves cannot travel through the liquid outer core of the earth and cannot be detected at the opposite point on the earth.

6 Explain what causes a tsunami Explain why scientists find it difficult to predict when a tsunami may happen. Geologists use sound waves from a small explosion to search for oil underground. A small explosion is triggered at the Earth's surface. The waves reflect back from the top of the oil field. Suggest why the waves are reflected from the oil field. Tsunamis are caused by underwater earthquakes / volcanic eruption (1) and are random (1) Because it is impossible to predict earthquakes (1) as there is no pattern to when movements occur (1) and they are not able to predict force needed to make tectonic plates move (1). Seismic waves Because there is a difference/change in density (1) What is the difference between current and voltage? An electric current is the rate of flow of State the unit in which electric current is usually measured. Describe what happens inside a generator to produce a current. State one way in which the size of the current could be increased. A generator is connected to a lamp. The generator is turned faster. Explain what happens to the lamp. Describe the difference between direct current and alternating current. State the difference between the currents which makes one alternating and the other direct. P1 Topic 5 Core Questions Current is the rate of flow of charge and voltage is the electrical pressure giving a measure of the energy transferred. Charge Ampere(s), amp(s), A A magnet (1) spins/turns (1) in/near) a coil of wire (1) OR A coil of wire (1) spins/turns (1) in a magnetic field You can increase the size of a current by increasing the strength of magnet (1); increasing number of coils/turns of wire (1) or increasing the speed of rotation (1) The light bulb would increase in brightness (1), due to an increased voltage (1) With direct current the flow of charge is only in one direction (1) whereas with alternating current the flow of charge changes (1) Alternating current can take positive and negative values RA (1) What is the name of the device used to change the size of an alternating voltage? The output from the solar panel is 60 V. State why a transformer cannot be used to increase this voltage. Describe what change happens when a step-up transformer is used. Why is electrical energy transmitted at high voltages? Where would step up and step down transformers be used in the national grid? What unit is electrical energy from the mains measured in? What is power and what units is it measured in? What are the standard units for energy transferred? A small notebook computer has a power rating of 40 W. How much energy is supplied to the computer each second? Describe how electrical energy is obtained from one named renewable resource. One type of solar panel uses the Sun's energy to produce electricity. Which energy transfer takes place in a solar cell? What is a renewable and non-renewable energy source? Transformer Transformers only change alternating voltages/currents and will not work with direct current As the voltage increases (1) the current decreases(1) It improves efficiency by reducing heat loss in the transmission lines by allowing a lower current to be used. Step up transformers are used in power stations whereas step down transformers are used before electricity enters factories and again before it enters homes, offices and shops. Kilowatt-hours It is the rate of transferring energy. It is measured in Watts (W). Joules (J) 40J Any of the following: Hydroelectric Geothermal Wind turbine Light to electrical Non-renewable: Once it has been used it has been effectively lost. (Examples include coal, oil and gas (fossil fuels) and uranium.)

7 What are the advantages of non-renewable sources of energy? What are the disadvantages of renewable sources of energy? Renewable: It can be used again and again. (examples include: wind, wave, solar, geothermal, hydroelectric, bio fuels etc.) Possible to generate large amounts of electricity reliably and relatively cheaply. Not always reliable, often expensive, don t generate a lot of electricity in comparison to non-renewables. Name 9 different types of energy. The athlete gets the energy he needs for his jump from his food. The form of energy stored in food is Which forms of energy does the athlete have at the top of his jump? Describe the energy transfer taking place in a loudspeaker. A student uses a solar powered battery charger to charge some batteries. What is the form of energy transferred into the battery charger? Can energy be created? The students read the statement: All the energy supplied to the motor eventually ends up as thermal energy in the surroundings. This statement best describes the idea of Some students investigate the efficiency of electric motors. One of the students states that all of the energy supplied to a motor is transferred into other forms. This statement is one example of the idea of What is efficiency? How does a system remain at a constant temperature? When the heater is switched on, it quickly warms up and then stays at a constant temperature. Explain why the heater stays at a constant temperature. The electric motors which drive the wheels are painted black. Suggest why the motors are painted black State why the pipes in the solar water heater are painted black. The hosepipe is painted black because blackened surfaces are A solar powered shower uses a plastic bag containing water; the instructions are to leave the bag out in sunlight during the day. Explain what colour the bag should be to heat the water to the highest temperature. P1 Topic 6 Core Questions Light, thermal (heat), sound, electrical, Kinetic (movement), chemical, gravitational potential, elastic potential, nuclear. Chemical energy gravitational potential and kinetic A loudspeaker transfers electrical energy (1) into sound energy (1) light energy electrical energy chemical energy (1) No, it can only be transferred. Energy is conserved. conservation of energy conservation of energy A measure of how much of the energy is transferred into a useful energy type. It needs to radiate the same average power (measured in Watts (W)) as it absorbs. An explanation linking dissipating heat (1) at same (rate)/s quickly as energy is being supplied (1) Any one from black is a good thermal radiator (1) (helps to) prevent motors overheating (1) Black is a good absorber of heat energy (1) as it absorbs more infrared radiation (1) good absorbers of radiation The bag should be black (1) because black is a good absorber of thermal radiation (1) P1 Keywords and Definitions keywords Converge Converging Lens Convex Lens Eyepiece lens Focal length Geocentric Heliocentric Image Definitions When rays of light come together towards a point. A lens which focuses light inwards onto a point. Also called convex. A lens which focuses light inwards onto a point. Also called converging. The lens found in the place you look into on a telescope. The distance between lens and focussed image. Earth at the centre. The Sun at the centre. The visable reproduction of an object, e.g. by a lens.

8 Interface Lens Light waves Magnifications Magnified Magnify Microwaves Naked eye Normal Objective lens Orbits Primary mirror Radio waves Real image Reflected Reflecting telescope Refracting telescope Refraction Telescope Transfer Transverse waves Virtual image Visible light Alpha (α) particles Amplitude Beta (β) particles DNA Electromagnetic radiation Electromagnetic spectrum Electromagnetic waves Fluorescence Fluorescent lamps Frequency Gamma rays Hertz (Hz) Illuminated Infrared Infrared radiation (IR) Ionising radiation Ions Longitudinal waves Mutations Negative powers Optical fibre Radioactive The point where two things interact or meet. An object that refracts light in a way that makes it diverge or converge. The name given to waves in the EM spectrum that we can see. Enlargements. Made bigger by a lens. To enlarge an image. The waves in the EM spectrum that can be used for heating water and sending signals. The body part that can be used to look into the night sky. The imaginary line at right angles to a surface. A lens which magnifies the image. The curved path an object follows around another object in space. The curved mirror in a telescope that light first reflects off. The name given to waves in the EM spectrum that have the longest wavelength. An image which can be projected onto a screen. "Bounced" off a surface. A telescope that uses a curved mirror and lens. A telescope which uses lenses and not mirrors. The name given to light changing speed and direction between two materials. A device used to study space. Move from place to place. Waves where the movement is at right angles to the direction of travel. An image which appears to exist if you look through a lens but you cannot project. The part of the electromagnetic spectrum that we can see. Helium nuclei (2 protons and 2 neutrons). The "height" of a wave or how much it is displaced. High speed electrons. An acid which makes up a code that gives us our genetics. Any emitted part of the EM spectrum. The spectrum of light - visible and not visible. "Light waves" found anywhere in the EM spectrum. Giving off light. A lamp that gives off light. How many waves pass per second. The region of the spectrum that kills cells and can be very harmful. The unit for frequency meaning once per second. Lit up. The region of the electromagnetic spectrum that is produced by all objects with heat. The region of the electromagnetic spectrum that is produced by all objects with heat. Radiation that can cause particles to gain a charge by losing electrons or an electron. A particle with a charge (due to an unbalanced number of electrons). Waves where the movement is along the direction of travel. When the DNA of a cell is altered. A power in maths that has a negative value. A glass strand that can allow light to pass through it. Something which gives off ionising radiation.

9 Radiotherapy Seismic waves Skin cancer Sound waves Thermal imaging Ultraviolet Ultraviolet radiation (UV) Vacuum Wave speed Wavelength X-rays Big Bang theory Black hole Cosmic microwave background (CMB) radiation Dense Doppler Effect Fusion reactions Galaxy Landers Main sequence Milky Way Nebulae Neutron star Nuclei Pitch Protostar Red giant Red supergiants Red-shift Rovers Search for Extraterrestrial Intelligence (SETI) Solar System Space probes Spectrometer Spectrum Stars Steady State theory Supernova Universe Visible light White dwarf Treating someone with radiation. Waves created by earthquakes. An illness caused by mutations in skin cells. Waves generated by noise. Making an image based on the heat given off by something. The region of the electromagnetic spectrum that is next to violet but can't be seen. The region of the electromagnetic spectrum that is next to violet but can't be seen. A space with no particles in it. The speed of the wave. The length of a wave. The region of the spectrum used to take medical images of bones. The idea that the Universe quickly expanded from a point in space and no new matter is created. A dead star creating so much gravitational pull that even light is pulled in. Radiation found evenly spread throughout the Universe. Tightly packed. The effect heard when an ambulance comes towards you then moves away. A reaction where hydrogen become helium and releases energy (like in stars). A collection of millions of stars that are close together and possibly orbit a black hole. Something which goes to another planet. The normal life cycle a star follows. The galaxy in which we live. Huge clouds of gas in space. A dead star that is very dense. The centres of things (including atoms). Effectively means frequency. The beginnings of a new star. A main sequence star that is getting older and bigger. A larger star that is getting older and bigger. When light looks more red because of a stretched wave length. Something which moves around on another planet. A project that searches for intelligent life in space. A collection of stars and planets in orbit of each other. Something which we send into space looking for things. Something that measures a spectrum, looking for dark lines in it. In terms of light this means all of the groups of light. It can mean a rainbow. Balls of gas in space that emit light due to the nuclear reactions within them. The idea that the Universe has always existed but gets bigger with new matter being made. A huge explosion from a dying star. Everything that exists. The light which we can see. The remnants of a dead main sequence star.

10 Convection currents Core Crust Earthquakes Epicentre Focus Frequency Infrasound Mantle Medium P waves Refracted S waves Seismic waves Seismometers Sonar Sound wave Tectonic plates Tsunami Ultrasound Ultrasound scan Acid rain Alternating current (AC) Carbon brushes Climate change Current Decommissioned Direct current (DC) Dynamos Efficiency Electricity Electromagnetic induction Electromagnets Fossil fuels Generator Geothermal energy Hydroelectricity Induced current Joule (J) Kilowatt-hour (kwh) Kilowatts (kw) Magnetic field National Grid Non-renewable resources Nuclear power Power The way in which heat "moves" in the mantle, rising and falling. The centre of the Earth. The outer layer of the Earth made up of rock. A tremor resulting from movement in the Earth's crust. The point at the surface directly above the focal point of an earthquake. The point where a seismic wave began. How many waves pass in a second. Low frequency sound (below 20Hz). The layer below the Earth's crust made of molten magma. A material through which something passes. Longitudinal (and faster) seismic waves. Waves that have changed speed and direction at the boundary between two materials. Transverse (and slower) seismic waves. A wave which travels through the Earth. A device used to measure the size of waves travelling through the Earth. A system used to see how deep water is (or look for objects in water). A wave caused by noise. The large area of the Earth's crust that move slowly. Water waves caused by movement in the Earth's crust. High frequency sound (above 20,000Hz). A scan using high frequency sound waves. Rain with a lower ph. Current which flows "back and forth" or in different directions. Connectors used to maintain a good contact with the dynamo as it spins. The change to the temperature and weather of the Earth. The flow of charge/electrons. Not used any more and shut down/disused. Current which flows in one direction only. A device which used movement (kinetic energy) to create electricity. How much energy is transferred usefully compared to how much is wasted. The flow of charge/electrons, often in a wire. The creation of electrical current by moving a magnet along/around a wire. A magnet created using an electrical current. Fuels from fossilised plants and animals (coal, oil and natural gas). A device which produces electricity. Energy from hot rocks beneath the Earth's surface. Electricity produced by water turbines in dams of reservoirs. Current created by a magnetic field being moved along a wire (like in a dynamo). The measurement of energy. A measurement of electricity use in a home meaning 1000W being transferred in an hour. A thousand watts (1000W). A field caused by a magnet with a north and south. The wires and transformers that supply electricity around the country. Energy resources from sources that cannot be replenished (can run out). Energy from nuclear materials like uranium. The rate (speed) at which energy is transferred.

11 Primary coil Renewable energy resources Secondary coil Slip rings Solar cells Solar energy Step-down transformer Step-up transformer Tidal power Transformer Unit Voltage Watt (W) Wave power Wind turbines Chemical potential Cost-efficient Elastic potential Electrical Energy transfer Gravitational potential Kinetic Law of conservation of energy Light Nuclear potential Payback time Sound System Thermal Topic 1 The coil of wire carrying electrical current entering a transformer. Energy that comes from a source that is continually replenished (isn't running out). The coil of wire carrying electrical current leaving a transformer. Connection rings found on a dynamo. A cell that produces electrical current when sunlight is absorbed by it. Energy that comes from sunlight. A device which decreases the voltage of AC current. A device which increases the voltage of AC current. Energy from the rising and falling tide. A device which changes the voltage of AC current. The measurement of electricity use in a home. The "pressure" in a circuit, sometimes called the potential difference. The unit for power, also meaning joules per second. Energy from waves. Turbines that are turned by the wind (like windmills). Energy potential in chemicals. Pays for itself with the savings it makes. Energy potential in something elasticated. Energy which is the flow of electrons. The change of energy from one for to another. Energy potential as you move up through gravity or higher. Movement energy. The law that energy is never lost. The form of energy we see. Energy potential in radioactive materials. The time it takes for the savings of a new device to cover the cost of buying it. Energy we hear. Connected processes that make up a bigger whole. Heat energy. P2 Core Questions Name 3 sub atomic particles Name the mass and charge of a proton Name the mass and charge of an electron Name the mass and charge of a neutron What sub-atomic particles are found in the nucleus? What sub-atomic particles are found in orbits outside the nucleus? Opposite/unlike charges... Same/like charges... Describe how static electricity is formed What charge does an object which has gained electrons have? What charge does the object which has lost electrons have? Explain how static electricity induces a charge Protons, neutrons and electrons, Mass 1, charge positive Mass 0, charge negative Mass 1, charge neutral Protons and neutrons Electrons Attract Repel Friction between 2 insulators causes electrons to move from one material to another. Negative Positive A negative object is brought near a neutral object; it repels the negative electrons leaving a positive charge on the neutral object. The negative object is attracted to the now positive object.

12 Name 3 uses of static electricity Describe how static electricity is used to spray paint Suggest benefits to using static electricity for spray-painting or insecticides Explain how static electricity builds up in aircraft What are some of the potential dangers of electrostatic charges? How are aeroplanes refuelled safely Describe the movement of electrons when you get a static electric shock Why are metals good conductors? What is current? What is electric current? Describe a direct current State objects that would produce a direct current Describe an alternating current How do you calculate charge? What unit do we measure charge in? Topic 2 What is the unit for current, how do you measure it and how do you place it in a circuit? What is the unit for potential difference, what equipment do you use to measure it and how do you place it in a circuit? What happens to current in a series circuit? What happens to the voltage in a series circuit? If the potential difference across V2 is 2.5V and across V3 is 2.5V, what is the potential difference across V1? Spray painting cars, chimney precipitators, spraying insecticide (charges can be the other way around) Paint is given a negative charge; they repel each other and form a mist of paint. The car is given a positive charge; the negative paint attracts to the positive car and coats it. Less waste of paint Saves money Friction, caused by the plane colliding with particles in the atmosphere, causes electrons to build up in the body of the aircraft as it is insulated and these electrons cannot be earthed. -Fuelling aircraft- static builds up in the nozzle and could spark and ignite the fuel causing an explosion -Lightning -Flying aircraft The aeroplane and the tanker are earthed using a metal wire to discharge any build up of electrons Electrons are built up in you as your shoes/jumper rub against something, when you touch a conductor you get an electric shock as electrons flow from you through the conductor and to the Earth. They contain a sea of delocalised/free electrons, which are free to move The flow of electrons The rate of flow of electrons The flow of electrons in one direction A battery, a cell, a dynamo Electrons moving back and forth millions of times a second Charge = current x time Coulombs (C) Measured in Amps (A), using an ammeter which is placed in series in a circuit Measured in Volts (V), using a voltmeter which is placed across a component (parallel to a component) The current is always the same throughout a series circuit The voltage provided by the power pack/battery is shared between the components in the series circuit 5V V1 = V2 + V3 If A1 read 3A, what would the current at A2 and A3 be? 3A What happens to the current in a parallel circuit? What happens to the voltage in a parallel circuit? The current splits/divides at a junction and recombines at a later junction The voltage across the powerpack/battery is the same across all components in a parallel circuit

13 If A1 = 3 A and A2 = 1A, what is the current measured at A3 and A4? A3 = 2A A4 = 3A (because the current after the junction must always equal the current before the junction) If V2 has the potential difference of 5V, what is the potential difference of V1 and V3? They are both 5V What happens to the current if you increase the potential The current increases difference (voltage) of a power pack/battery If you increase the resistance in a circuit, what happens to It decreases. the current? How do you calculate resistance? Resistance = voltage / current R = V/ I What is the unit for resistance? Ohms (Ω) Determine the resistance of this circuit if the current is 2.5A and the voltage is 3V Equation: R = V/ I Substitute: R = 3V / 2.5A Calculate: 3 / 2.5 = 1.2 Units: R = 1.2 Ω If the current in a circuit is 1.4A, and the resistance is 3Ω, what is the potential difference in the circuit? Figure out the current when the resistance is 2.5Ω and the voltage is 13V. Explain why the resistance of a filament lamp changes as it gets hot? How does a diode work? How does the current vary with voltage for a diode? What is an LDR? How does the resistance of a light dependant resistor change with light intensity? What happens to the resistance and current in a thermistor as you increase temperature? How does the current vary with voltage for a filament lamp as it warms up? Which of the following graphs shows how current varies with potential difference for: 1) Filament lamp 2) Diode 3) Fixed resistor Equation: V = I x R Substitute: V = 1.4A x 3Ω Calculate: 1.4 x 3 = 4.2 Units: V = 4.2V Equation: I = V / R Substitute: I = 13V / 2.5Ω Calculate: 13 / 2.5 = 5.2 Units: I = 5.2A The resistance of a filament lamp increases as it gets hot because the metal ions in the filament vibrate faster causing more collisions with the moving electrons, decreasing current. It only allows current to pass through it in one direction. When the current is flowing in the right direction, the current increases voltage increases but it is not directly proportional (not a straight line on the graph). The gradient of the graph increases as current increases, because as the diode gets hotter (from the greater current) its resistance increases. Light dependent resistor. As light intensity increases, the resistance decreases. As the temperature increases, the resistance decreases, which increases the current (flow of electrons) As a bulb heats up the resistance increases and so, as current increases voltage increases but it is not directly proportional (not a straight line on the graph). The gradient of the graph increases as current increases. This is because as the bulb gets hotter its resistance increases, until it reaches its maximum temperature. 1) Filament lamp graph a 2) Diode graph c 3) Fixed resistor graph b

14 What does resistance transfer electrical energy into? Name a device where the heating effect of an electric current is useful. Name a device where the heating effect of an electric current is not useful. What is the unit for electrical power? What is the unit for energy transferred? What is power? What unit do we measure power in? How can you calculate power using the energy transferred in an object and the time it is used for? What is the power of a device if it transfers 18,000J of energy in 10 minutes? How long is a 50W device used for if it transfers 1.5kJ? How much energy is transferred when a 500W device is used for half an hour? Thermal energy (heat) Toaster, kettle, oven... Light bulb Watt Joule The rate of energy transferred from one form to another/others. Watts (W) Power = Energy transferred/time taken P = E / t Equation: P = E / t Convert: time needs to be in seconds, 10 minutes x 60 = 600s Substitute: P = 18,000J / 600s Calculate: 18,000 / 600 Units: P = 30W Equation: t = E / P Convert: Energy needs to be in J: 1.5kJ x 1000 = 1500J Substitute: t = 1500J / 50W Calculate: 1500 / 50 = 30 Units: t = 30s Equation: E = P x t Convert: Time needs to be in seconds: 0.5 hours x 60 = 30 minutes x 60 = 1800s Substitute: E = 500W x 1800s Calculate: 500 x 1800 = 900,000 Units: E = 900,000J How can you calculate power using current and voltage? Power = Current x voltage P = I x V A kettle uses the mains electricity at 230V. The current is 13A. What is the power of the kettle? What is the current flowing through a 36W device using a 12V power supply? What is the voltage of the power supply for a 144W device which has current of 16A flowing through it? How is energy calculated using an equation? (hint: combine the power calculations together!) What is the energy transferred when a radio uses a 12V supply for 15 minutes, and has a current of 3A? Equation: P = I x V Substitute: P = 13A x 230V Calculate: 13 x 230= 2990 Units: P = 2990W Equation: I = P / V Substitute: I = 36W / 12V Calculate: 36 / 12 =3A Units: I = 3A Equation: V = P / I Substitute: V = 144W / 16A Calculate: 144 / 16 = 9 Units: V = 9V Energy = Current x Voltage x time E = I x V x t Equation: E = I x V x t Convert: 15 minutes into seconds: 15 x 60 = 900s Substitute: E = 3A x 12V x 900s Calculate: 3 x 12 x 900 = Units: E = 32400J Topic 3 What is the unit for velocity? What is a vector quantity? m/s It has both a size (magnitude) and direction.

15 Give 5 examples of a vector quantity? How is speed calculated? A cyclist travels a distance of 1800m in 2 minutes. What is their speed? How long did it take for a car to travel 30 metres when travelling at 0.6m/s? A peregrine falcon can fly at speeds of 50m/s, at this speed how far can it travel in 7 seconds? Displacement, velocity, acceleration, force and momentum. Speed = distance / time Equation: S = D / t Convert: Time needs to be in seconds: 2 x 60 = 120s Substitute: S = 1800m / 120s Calculate: S = 1800 / 120 = 15 Units: S = 15 m/s Equation: t = D / S Substitute: t = 30m / 0.6m/s Calculate: t = 30 / 0.6 Units: t = 50s Equation: D = S x t Substitute: D = S x t Calculate: 50 x 7 = 350 Units: 350m Using a distance time graph, describe what is happening to the object between O and A, A and B and B and C? O and A: The object is accelerating forwards A and B: The object is stationary B and C: The object is moving backwards What is acceleration and its unit? How do you calculate acceleration? How do you calculate change in velocity? A car starts from 0m/s and reaches a velocity of 50m/s in 5 seconds, what is its acceleration? What is the change in velocity if an object accelerates at a rate of 2m/s 2 in 600 seconds How long did it take for a car accelerating by -2.5m/s 2 when its initial velocity was 70m/s and its final velocity was 20m/s. Give 2 examples of how an object can accelerate. Describe the motion of each objects on these velocity-time graphs Acceleration is the rate of change of speed, its unit is m/s 2 Acceleration = change in velocity / time Change in velocity = final velocity initial velocity v u Equation: A = (v u) / t Substitute: A = (50m/s 0m/s) / 5 Calculate: A = 50 / 5 Units: 10 m/s 2 Equation: (v u) = A x t Substitute: (v u) = 2m/s 2 x 600s Calculate: 2 x 600 = 1200 Units: (v u) = 1200m/s Equation: t = (v u) / A Substitute: t = (20m/s 70m/s) / -2.5m/s 2 Calculate: -50 / -2.5 = 20 Units: t = 20s 1) If it s speeding up or slowing down. 2) If it s changing direction. 1) The object is accelerating quickly 2) The object is moving at a constant speed 3) The object is decelerating 4) The object is stationary Describe how to calculate the distance an object has travelled using a velocity-time graph Name a force By measuring the area under the graph Friction/drag/air resistance/water resistance Weight/gravity Thrust/upthrust/ Reaction Lift

16 When 2 forces (action and reaction forces) interact with each other, what effect do they have? Describe the motion of each 4 objects When action and reaction forces interact they exert a force that is equal in size and opposite in direction to each other A: Stationary B: Accelerating C: Constant speed D: Decelerating What are the forces in this free-body diagram? 1= reaction 2= gravity What are the forces in this free-body diagram? 1= reaction 2= thrust 3= gravity 4= friction/air resistance/ drag If the forces acting on an object are balanced and the resultant force is zero, what is the motion of the object? If the forces on an object are unbalanced, how will it behave? What is resultant force? What is the resultant force of this object? What is it s motion? Stationary or constant speed It will accelerate in the direction of the resultant force. The total force that results from 2 or more forces acting on an object 10N to the left The object is decelerating A cyclist applies 100 N of thrust to a bike and is battling against 75 N of wind resistance, how would you describe their motion and what is the resultant force? What 2 factors affect the size of the acceleration of an object? F=ma what does it stand for, what are the units for F and m? A 1500kg car has an acceleration of 3.0m/s 2, what is the force provided by the engine? A car accelerates at 6m/s² as its engine provides a force of 7,800 N. What is the mass of the car? A jumbo jet has a mass of 40, 000,000g. If its engines produce a force of 800, 000 N, what will its acceleration be? They are accelerating with a resultant force of 25N acting in forwards direction. The mass of the object and the size of the force accelerating the object forwards Force = mass x acceleration Force unit is Newtons (N) Mass unit is kilograms (Kg) Equation: F = M x A Substitute: F = 1500kg x 3m/s 2 Calculate: 1500 x 3 = 4500 Units: F = 4500N Equation: M = F / A Substitute: M = 7,800N / 6m/s 2 Calculate: M = 7,800 / 6 Units: M = 1,300kg Equation: A = F / M Convert: Mass needs to be in kg, 40,000,000 / 1000 = 40,000 Substitute: A = 800,000 / 40,000kg Calculate: 800,000 / 40,000

17 What is the difference between mass and weight? What is terminal velocity? Describe how the forces acting on a ball change as it starts to fall from the sky How do you calculate the weight of an object? What is the weight of a 300kg planetary landing craft on the surface of the Earth? What is the mass of an object if the weight is 120N on Jupiter whose GFS is 25N/kg? What is the GFS of Mars if a 150kg object has a weight of 570N? Units: A = 20m/s 2 Mass never changes, it is a measure of the amount of matter that makes up an object whereas weight depends on the gravitational field strength of a planet The point at which the weight and air resistance are balanced and the object can accelerate no more. At the start of the fall the downward force (weight) is greater than the upward force (air resistance). The weight remains constant but the air resistance increases as the ball accelerates until the weight is balanced out by the air resistance. At this point the ball is moving at a constant speed, this is known as the terminal velocity. Weight (N) = mass (kg) x gravitational field strength (N/kg) Equation: W = M x GFS Substitute: W = 300kg x 10N Calculate: 300 x 10 = 3000 Units: W = 3000N Equation: M = W / GFS Substitute: M = 120N / 25N/kg Calculate: M = 120 / 25 = 0.48 Units: M = 4.8kg Equation: GFS = W / M Substitute: GFS = 570N / 150kg Calculate: 570 / 150 = 3.8 Units: GFS = 3.8N/kg Topic 4 How do you calculate the stopping distance of a car? List four factors that affect the thinking distance of a driver Stopping Distance = Thinking distance + Braking distance alcohol/other drugs, tiredness, distractions, age, List 5 factors that affect the braking distance of a car Quality of brakes, mass of vehicle, speed of vehicle, state of the road, the amount of friction between the tyre and road surface (affected by weather and tyre condition). What is momentum? Momentum is a measurement of the velocity and mass of a moving object. Name 3 ways we can change the momentum of an object 1. Changing the size of an object 2. Changing the speed of an object 3. Changing the direction of an object What is the unit for momentum? Kg m/s How do you calculate momentum? Momentum = mass x velocity A 1200kg car travels along at 12 m/s, calculate its momentum. Calculate the velocity of a 250kg object if it s momentum is 5000 kg m/s. Calculate the mass of an object which has the momentum of 54, 000 kg m/s and travels at a velocity of 12m/s. What features do cars have to reduce the rate of change of momentum of passengers when the car brakes sharply or has a collision? Why do seat belts, crumple zones and air bags make collisions safer? Equation: Mo = Ma x V Substitute: Mo = 1200kg x 12m/s Calculate: Mo = 1200 x 12 = Units: Mo = 14,400 kg m/s Equation: V = Mo / Ma Substitute: V = 5000 kg m/s / 250kg Calculate: V = 5000 / 250 = 20 Units: V = 20 m/s Equation: Ma = Mo / V Substitute: Ma = 54,000kg m/s /12m/s Calculate: Ma = 54,000 / 12 = 4500 Units: Ma = 4500 kg Seatbelts, crumple zones, air bags. They increase the time taken for the person in the vehicle to stop; this reduces the size of the force acting on a person.

18 What is the law of conservation of momentum? A ball with momentum of 10kg m/s hits a stationary object, what is the total momentum of the balls after the collision? HIGHER) How can you calculate the force of an object during a collision? HIGHER) What force is needed to get a 25 kg stationary bicycle moving from 0m/s to 12 m/s in 5s? How can you increase an objects gravitational potential energy? How do you calculate work done? What is work done? What is the unit for work done? Sharon lifts a 5N weight 50cm, how much work is done? What is the force if the work done is 30J when an object is moved 4m? Calculate the distance an object when it is moved with a force of 30N, if the work done is 900J. What is a definition of power? What is the unit for power? How do you calculate power? What can be measured in joules per second? The rate of doing work is called... Calculate the power of an object if the work done is 800J in 400s What is the work done if a 500W crane moves a box in 1,800s? How fast can a 1,600W machine move an object which would require 32,000J? How can you combine work done = force x distance and power = work done / time A motorbike accelerates over 40m, it uses a force of 6000N and takes 5 seconds to travel the 40m. What power did the engine produce? The total momentum before a collision is the same as the total momentum after a collision 10kg m/s Force = Change in momentum / time Momentum at start = 0 12 = 0 kg m/s Momentum at end = = 300 kg m/s Change in momentum = = 300 kg m/s Equation: Force = change in momentum time Substitution: Force = 300kg m/s 5s Calculation: Force = = 60 Units: Force = 60N Increase the objects height Work done (J) = Force (N) x Distance (m) It is the amount of energy transferred Joules Equation: WD = F x D Convert: distance needs to be in metres= 50cm becomes 0.5M Substitute: WD = 5N x 0.5 Calculate: 5 x 0.5 = 2.5 Units: WD = 2.5J Equation: F = WD / D Substitute: F = 30J / 4m Calculate: 30 / 4 = 7.5 Units: F = 7.5N Equation: D = WD / F Substitute: D = 900J / 30N Calculate: 900 / 30 = 30 Units: D = 30m The amount of energy transferred every second (Joule per second (J/S)) Watt (W) Power = work done / time Power Power Equation: P = WD / t Substitute: P = 800J / 400s Calculate: 800 / 400 = 2 Units: P = 2W Equation: WD = P x t Substitute: WD = 500W x 1,800s Calculate: 500 x 1,800 = 900,000 Units: WD = 900,000s Equation: t = WD / P Substitute: t = 32,000J / 1,600W Calculate: 32,000 / 1,600 = 20 Units: t = 20s Power = (force x distance) time Equation 1: Work done = F x d Substitute: Work done = 6000N x 40m Calculate: Work done = 240,000 J Equation 2: Power = work done / time taken Substitute: Power = 240,000J / 5 Calculate: Power = 240,000 / 5 = 48,000 Units: Power = 48,000W or 48kW Or Equation: P = (F x D) / t Substitute: P = (6000 x 40) / 5

19 A cart on a rollercoaster sits stationary at the top of a steep drop. Which type of energy does it have a lot of? What is the value of this energy equal to? As the cart rolls down the track, what is this energy converted to? Name 9 different types of energy. Energy transfers are never totally efficient, which type of energy is most often lost to the surroundings in an energy transfer? At which point will the ball have the maximum/greatest gravitational potential energy? Calculate: 240,000 / 5 = 48,000 Units: 48,000W Gravitational Potential Energy (GPE) The work done moving the cart to the top of the ride. Kinetic, thermal (heat) and sound energy Kinetic, gravitational potential, electrical, chemical, nuclear, sound, light, heat, elastic Heat B has the greatest gravitational potential energy What energy changes are occurring between B and C? Gravitational potential energy is decreasing as it transfers into an increasing amount of kinetic energy, thermal energy and sound energy How do you calculate gravitational potential energy? GPE (J) = mass (kg) x gravitational field strength (N/kg) x height (m) What is the gravitational potential energy gained by a 500kg Equation: GPE = m x gfs x h car is lifted 15m on Earth (GFS=10N/kg)? Substitute: GPE = 500 x 10 x 15 Calculate: 500 x 10 x 15 = Units: GPE = 75,000 J How do you calculate kinetic energy? Kinetic energy = ½ x mass x velocity 2 What is the kinetic energy transferred by a 2kg dog walking Equation: KE = ½ x m x v 2 2m/s? Conversions: 2m/s x 2m/s = 4m/s 2 Substitute: KE = ½ x 2kg x 4m/s 2 Calculate: KE = 0.5 x 2 x 4 Units: KE = 4J Topic 5 What is alpha radiation? What is beta radiation? What is gamma radiation? What is an ion? How do atoms form ions? When an unstable nucleus emits ionising radiation is it a random or predictable event? Which is most highly ionising type of radiation? Which is more penetrating type of radiation? For each type of radiation, state what can stop it What is the atomic number? What is the mass number? What is an isotope? Do radioactive sources stay radioactive forever? Describe how nuclear fission produces thermal energy A Helium nuclei (two protons and two neutrons) An electron An electromagnetic wave A charged atom or group of atoms. By gaining or losing electrons. random Alpha Gamma Alpha: a sheet of paper, skin, a few cms of air Beta: 3mm aluminium, metres of air Gamma: Thick lead or concrete; kilometres of air The number of protons present. The relative mass of an atom which is equal to the number of protons and neutrons present. Two or more atoms of the same element (the same number of protons) but with a different number of neutrons. No- the activity of a radioactive source decreases over time 1) Uranium 235 nucleus absorbs a neutron 2) Nucleus becomes unstable 3) Nucleus splits (known as fission)

20 What is a nuclear chain reaction? What does the fission of U-235 produce? How are chain reactions controlled? How can you increase the amount of electricity being generated using the control rods in a nuclear reactor? How can you stop a nuclear reactor fully? What does the moderator do in a nuclear reactor What material is used for a control rod? What material is used for a moderator? What is the key benefits and disadvantages of using nuclear power to generate electricity? How is thermal energy from a nuclear reactor used to generate electrical energy in a power station? What is nuclear fusion? Describe what happens during nuclear fusion Where is fusion found naturally? What are the conditions required for fusion and where does it normally occur? Why is it extremely difficult to initiate nuclear fusion? Why can we not make a nuclear fusion power station? When is a new idea accepted by the scientific community (e.g. cold fusion) Explain the phrase validated by the scientific community. 4) Into 2 daughter nuclei (of similar size) (Kr & Ba) 5) 2 or more neutrons released 6) Energy is released Where the neutrons produced by a fission reaction trigger further nuclear fission reactions. This increases in number of fission reactions as more neutrons are produced. Two daughter nuclei and two or more neutrons and a large amount of energy. Control rods are lowered to absorb excess neutrons By moving the control rods out of the reactor, fewer neutrons are absorbed and so more fission reactions occur. This produces more thermal energy which enables more electricity to be generated By lowering the control rods all the way to the bottom of the nuclear reactor, all neutrons produced by fission reactions will be absorbed and so no further reactions will occur, stopping the nuclear reactor from producing energy. It slows neutrons down so they can be absorbed by a uranium nucleus and result in another fission reaction. Boron Graphite Benefits: no direct CO2 emissions Disadvantages: public perception, risk, safety issues and radioactive waste disposal, use of nuclear materials in terrorism. Thermal energy from the nuclear reactor turns the water into steam. This turns a turbine which in turn turns a generator (a coil of wire inside a magnetic field), generating electricity. Reaction caused when the nuclei of light atoms like Hydrogen join together to make the nucleus of a heavier atom like helium. 2 hydrogen nuclei join/fuse together to form helium nuclei which releases thermal energy In stars At very high temperatures, very high pressures and densities, the hydrogen nuclei need to collide at very high speeds so they have lots of kinetic energy. Both helium nuclei have positive charges This means they repel each other This reduces possibility of successful collisions to form helium, a neutron and also the energy The rate of fusion is too small to be useful for generating electricity. It is impossible to raise the temperature to the required level for enough reactant to make the reaction self-sustaining. When it can be validated The procedure has been checked to confirm consistent results by other reputable scientists /organisations / peers. Topic 6 What is the unit of activity of a radioactive isotope? Why is ionising radiation dangerous? What precautions should be taken when handling radioactive substances? The nuclear power industry creates a lot of radioactive waste, what are the options for disposal? The Bequerel (Bq) is the number of emissions every second. It can lead to tissue damage, burns, DNA mutations and cancer. Handle with tongs, protective clothing, never point a source at yourself or others. The risk is reduced with increased distance. Bury - probably best. Dump at sea - not preferable because over time the containers will corrode and leak radiation into the sea which could then get into the food chain.

21 Launch into space - expensive and not preferable because if the launch goes wrong it will scatter radioactive material over a large area of earth. The products of nuclear fission are radioactive. Some remain radioactive for a many years. Long term storage and Why is this problem? disposal is problematic. What are some of the risks of using nuclear power? Rods are radioactive which can cause cancer Danger of accident during transport Workers could be exposed to radiation Can damage environment if not properly contained Materials being disposed of are radioactive for long periods of time Water causing corrosion / leaks of radioactive waste Security from terrorist activity Leakage of radioactivity Contamination of ground, sea water, lakes, rivers, crops, fish, animals, drinking water What are some precautions we can take to reduce Long term storage, underground /under the sea the risk of using nuclear energy to generate Radiation shielding, lead/steel/concrete/ containers, sealed in glass. electricity? Shielding to protect people from radiation Security can be used to prevent public access to nuclear power stations Vehicle transporting radioactive materials need to be protected against damage Special disposal facilities needed, not landfill sites Need to be kept secure while decaying to safe levels Some materials have a shorter half-life, so long term storage is not necessary What are some of the advantages and Advantages: disadvantages of nuclear power? +Nuclear power plants do not produce carbon dioxide Disadvantages: -Processes used to make fuel rods require energy and generating this energy may cause carbon dioxide to be produced -Nuclear waste has to be stored for tens of thousands of years, nothing can be leaked during this time -Nuclear power is considered unsafe as radioactive material can be spread over cities and towns thousands of miles away What is half life? The time it takes for half the atoms in a radioactive sample to decay. How can we calculate half life on a graph? 1) Identify the initial count rate (let s say it is 80) 2) Divide this by 2 (80/2 = 40) 3) Draw a line on the graph from this value (40) 4) When you meet the line of best fit, draw a line to the x-axis 5) This is the half-life A sample of air contains 6 mg of radon. Radon has a half-life of 4 days. Calculate the mass of the radon remaining after 8 days. Where does background radiation come from? Why is radon gas a problem? How do you measure the radioactivity of a sample? The scientist takes several readings of background radiation. Explain why this is necessary to improve the accuracy of the investigation Give 5 uses of radioactivity and say which type of ionising radiation is used in each. Explain why gamma radiation is used for sterilising equipment and irradiating food Calculation of number of half-lives: 8 4 = 2 (half lives) Evaluation of mass: 6 2 = 3 2 = 1.5 (mg) Radioactive rocks (earth), cosmic radiation (space), hospitals and industrial uses. Released from some rocks and increases background radiation in some regions of the UK Take a reading of the background radiation (b) Measure the radioactivity of the sample (s) Subtract the background from the sample to get it s radioactivity (r) R = b - s More accurate Hard to measure a small activity Background radiation affects readings Need to find difference of two small quantities Can test smaller samples 1) Smoke alarms alpha 2) Irradiating food gamma 3) Sterilisation of equipment gamma 4) Tracing and gauging thickness beta 5) Diagnosis and treatment of cancer gamma. Gamma radiation kills microbes/bacteria/viruses on equipment and food.

22 Describe how smoke alarms work Explain how beta radiation is used to gauge thickness in materials Describe how gamma radiation is used to detect cancer. Describe how gamma radiation is used to treat cancers This prevents diseases being spread in hospitals and keeps food fresher for longer Alpha particles ionise air particles which completes the circuit in the smoke alarm. When smoke particles are produced, they absorb the alpha radiation which prevents the circuit from working and sets off the smoke alarm. Beta radiation is passed between paper, if the paper is too thick it will absorb more beta radiation and the count rate being detected will decrease. This increases the pressure of the rollers which makes the paper thinner, allowing beta radiation to pass through it again. The opposite occurs if the paper is too thin. Detect cancer: A tracer is taken by a person and is observed by a gamma camera. The gamma radiation shows areas of concerns and as it is very penetrating, the gamma radiation passes straight out of the body- it doesn t stay inside the person which prevents damage to their body. Gamma radiation beams are targeted at cancerous cells from many angles to reduce radiating surrounding healthy cells. The radiation kills the cancer cells. P2 Keywords and Definitions Keyword Discharged Earthing Electrostatic charge Induced charge Induction Neutrons Neutrons Nucleus Protons Static electricity Alternating current Ammeter Amperes (A) Coulombs (C) Current Diodes Direct current Filament lamps In parallel In series Definition To release a charge by a flow of electrons to earth (or neutral). Many electrical appliances have metal cases, including cookers, washing machines and refrigerators. The earth wire creates a safe route for the current to flow through, if the live wire touches the casing. The electric charge at rest on the surface of an insulated body (which establishes and adjacent electrostatic field). To make an object to become charged. The action by which a body possessing a charge of static electricity develops a charge of static electricity of the opposite character in a neighbouring body. A neutron is a subatomic particle contained in the atomic nucleus. It has no net electric charge, unlike the proton's positive electric charge. Particles in the nucleus with a mass of 1 and no charge, The central and most important part of an object, movement, or group, forming the basis for its activity and growth. A stable subatomic particle occurring in all atomic nuclei, with a positive electric charge equal in magnitude to that of an electron. A stationary electric charge, typically produced by friction that causes sparks or crackling or the attraction of dust or hair. In alternating current, the electrons don t move steadily forward. Instead, they just move back and forth. An instrument for measuring electric current Equivalent to one coulomb per second, formally defined to be the constant current The unit of electrical charge equal to the quantity of charge transferred in one second by a steady current An electric current is a flow of electric charge through an electrical conductor. Current will only flow through a diode in one direction only An electric current that flows continuously in a single direction As the temperature of the filament increases, the resistance increases making a curve. When the components of a circuit are parallel to each other when the components of a circuit are next to each other

23 Ions Light-dependent resistor (LDR) Ohms (Ω) Parallel circuit Potential difference Power Resistance Series circuit Thermistors Variable resistor Voltage Voltmeter Watts (W) Acceleration Action force Air resistance Displacement Distance-time graphs Drag Force Free-body diagram Gradient Gravitational field strength Interact Mass Reaction force Resultant Speed Terminal velocity Vector Velocity Weight Air bags Braking distance Crumple zones Crumple zones An atom or molecule with a net electric charge due to the loss or gain of one or more electrons. An LDR is a special type of resistor that changes its resistance depending on how much light there is Resistance unit A closed circuit in which the current divides into different paths before recombining to complete the circuit The difference of electrical potential between two points, measured in volts. The rate at which work is performed, or energy converted. Anything in the circuit which slows the flow down. A circuit that has its parts connected serially Similar to an LDR but its resistance depends on temperature, high temp low resistance and vice versa. Controls the magnitude of resistance passing through the resistor An electromotive force or potential difference (unit). An instrument for measuring electric potential in volts. The unit that measures power. Equal to one joule per second. A watt is equal to current x voltage. The rate of change of speed. A force that exerts a force on another object. It often comes in pairs with the Reaction Force, forming an action-reaction pairs. A force caused by air when an object is moving. How far something has moved in a straight line. A graph recording distance travelled over a particular time. A resistance to motion when an object moves through a medium. E.g. a boat moving through water. Strength or energy as an attribute of physical action or movement A pictorial device, often a rough working sketch, used by engineers and physicists to analyse the forces and moments acting on a body. How steep a line is. Gravitational field strength at a point is defined as the gravitational force per unit mass at that point. Act in such a way as to have an effect on another The amount of an object there is. A force that acts in the opposite direction to an action force. The result of two or more forces acting conjointly. How fast something is moving without a concern for the direction. Where the downward force of gravity equals the force of drag. A quantity that has a direction and size. How fast something is moving in a particular direction. The force with which an object near the Earth or another celestial body is attracted toward the centre of the body by gravity A safety device in a car, consisting of a bag that inflates automatically in an accident in order to increase the time it takes the person to slow down and reduce the force on their body. The braking distance is the distance taken to stop once the brakes are applied. A part of a motor vehicle, esp. the extreme front and rear, designed to crumple easily in a crash and absorb the main force of an impact. A part of a motor vehicle, esp. the extreme front and rear, designed to crumple easily in a crash and absorb the main force of an impact (by increasing the time it takes the vehicle to stop).

24 Energy transferred Friction Gravitational potential energy Joules (J) Kinetic energy Kinetic energy Momentum Power Reaction time Seat belt Stopping distance Thinking distance Vector quantity Watts (W) Work Alpha particles Atomic number Beta particles Chain reaction Control rods Core Daughter nuclei Decays Gamma rays Ion Ionising radiation Isotopes Mass number Moderator Nuclear fission Nuclear fusion Nuclear reactors Nucleon number Nucleons Penetration distance Proton number Radioactive The amount of energy being transferred from one place to another. The resistance that one surface or object encounters when moving over another. The energy that must be used against gravitational forces to move a particle of mass. The measurement of work done and energy transferred. This is the energy something has when moving. This is the energy something has when moving. The tendency of the object to keep moving in the same direction How quickly work is being done and therefore how quickly energy is being transferred. The time that goes by between a stimulus and the response to it. A safety device used in a car or plane to cause you to slow down over a longer period of time, thus reducing the force on the body in an accident. Stopping distance is the distance it takes for a car to stop from a specific speed. The thinking distance is the distance travelled in between the driver realising he needs to brake An amount or measurement that is related to a direction. Velocity, acceleration, and weight are vector quantities The measurement of power, it is equal to one joule per second. The amount of energy transferred doing something. Ionising radiation containing 2 neutrons and 2 protons (helium nucleus). The amount of protons that an element has. High-speed electrons that are emitted from an unstable nucleus A reaction which causes many others one after the other. Structures which absorb the neutrons, these are placed between the fuel rods in the core Where the fuel and control rods are placed and the reaction is occurring. The remaining nuclide left over from radioactive decay. When the nucleus of an atom breaks down causing it to emit radiation High frequency electromagnetic waves emitted by some unstable nuclei and so travel at the speed of light An atom which has gained or lost electrons. Radiation that causes atoms to lose electrons and become ions A different atomic form of the same element with the same number of protons but a different number of neutrons. The number of protons and neutrons in the nucleus of an atom. Something that slows down a nuclear reaction by slowing/absorbing neutrons. A nuclear reaction in which a heavy nucleus splits spontaneously or on impact with another particle, with the release of energy A nuclear reaction in which atomic nuclei of low atomic number fuse to form a heavier nucleus with the release of energy This transforms the energy contained in the nuclei of uranium and plutonium atom, into thermal energy using nuclear fission The number of protons and neutrons found in the nucleus of an atom. An alternative name for mass number. The particles found in the nucleus are called this. How far ionising radiation can travel through a substance. The number of protons that an element has. When a substance has an unstable nucleus, resulting in release or nuclear radiation.

25 Random Sub-atomic particles Unstable Activity Background count Background radiation Becquerel (Bq) Cosmic rays Count rate Electrostatic repulsion Geiger-Müller (GM) tube Half-life Hazards High level waste (HLW) Intermediate level waste (ILW) Irradiated Low level waste (LLW) Mutation Peer-reviewed Radioactive Radioactive decay Radioactive waste Radiotherapy Radon Risk Sterilised Tracer Validated Without a fixed time or pattern. The smaller particles that make up an atom. An atom which has too many neutrons could be said to be this. How much radiation is produced. The amount of background radiation. Small amounts of radiation in the atmosphere A unit of measurement, number of nuclear decays per second. The radiation emitted from space. Number of clicks per second or minute of ionising radiation When two of the same charges repel each other Measures intensity of radiation. The time taken for half the undecayed nuclei to decay. Dangers to a person or object Sealed in glass canisters and concreted over until the radiation becomes low level. Contained in metal cylinders because they become radioactive. To expose to radiation. For example to when you expose food to gamma rays to kill microorganisms you are irradiating the food. Not as radioactive, buried and compacted in special sites. The changing of a structure, resulting in a variant Reviewed by someone with knowledge on the subject Something that emits ionising radiation When an unstable radioactive nuclei decays and emits ionising radiation. Made up of radioactive daughter nuclei and radioactive isotopes formed when the materials in the core absorb neutrons The controlled use of high energy X-rays to treat many different types of cancer. In some cases, radiotherapy can also be used to treat non-cancerous tumours. A gas emitted produced by the natural decay of radioactive sources. E.g. Uranium. A situation involving exposure to danger To make something free from bacteria or other living microorganisms using Radiation These are used for tracking substances such as: -Find leaks or blockages in underground pipes -Find the route of underground pipes -Track the dispersal of waste To check or prove the accuracy of something P3 Core Questions Topic 1 How is physics used to diagnose medical problems? How is physics used to treat medical problems? Name one type of ionising radiation used in medicine. X-ray imaging, CAT scans, PET scans, Endoscopes and ultrasound scanning. Radiotherapy with gamma rays for cancer, lasers for skin and eyes, ultrasound for kidney stones and muscle problems. Radiotherapy with gamma rays.

26 Name one type of non-ionising radiation used in Endoscopes using visible light. medicine. What is radiation? Any type of energy that spreads out from a source, particles or waves. How is intensity affected by distance? Intensity decreases with distance (inverse square law applies here). How is intensity affected by the medium? Different materials absorb different amounts of energy and so affect intensity differently. Intensity = Power Area. What are the units? Intensity W/m 2. Power W and area m 2 If you were given the intensity and the power, Area = Power Intensity how could you calculate the area? What type of lens is a converging lens? A lens that is thicker in the middle to refract the light rays together and focus them at a point behind the lens. It will always have a positive focal length. What type of lens is a diverging lens? A lens that is thinner in the middle to refract the light rays away from each other and focus them at a point in front of the lens. It will always have a negative focal length. How is the power of a convex lens related to its shape? How is the power of a lens related to its focal length? Power of a lens = 1 Focal length. What are the units? In the lens equation, what do f, u and v stand for and in which unit are they all measured? What is a real image? What is a virtual image? Name the labelled parts of the eye: The thicker the lens, the more powerful it is. The more powerful the lens, the shorter the focal length. Power of a lens is measured in dioptres (D). The focal length is measured in metres (m). F= focal length, u = object distance, v = image distance. All measured in metres (m). An image that can be formed on a screen that is on the opposite side of the lens to the object. It is magnified and inverted with a positive focal length. An image formed on the same side of the lens as the object. It is magnified and the right way up. It cannot be projected onto a screen and the focal length is always shown as negative. How is light focused on the retina? Light enters the eye through the cornea where it is refracted. Light travels through the pupil and is further refracted by the lens to focus on the retina.

27 What is the job of the iris? What is the job of the ciliary muscles? What is the near point? What is the far point? What is short sight? What is long sight? How can short sight be corrected with glasses? How can long sight be corrected with glasses? Apart from spectacles, what other treatments are available for sight problems? Draw a labelled diagram to show reflection from a mirror. To control the size of the pupil and therefore control the amount of light entering reaching the retina. They contract and relax to change the shape of the lens, from thicker to thinner respectively, and so refract the light correctly to focus it on the retina, when looking at near and far objects respectively. The point nearest the eye at which an object can be focused. 25cm for a normal adult. The maximum distance a normal eye can see things. It is said to be at infinity. Can see close objects but not able to clearly see objects at a distance. It is often caused because the eyeball is too long or the cornea is too curved. Cannot see close up but can focus at a distance. This can be caused by old age because the lens becomes stiffer over time but can be because the eyeball is too short. Use diverging lens in the glasses. Use converging lens in the glasses. Contact lenses are lightweight and relatively inexpensive but they carry a risk of infection if not properly cleaned. Laser surgery is an expensive option and has the risk of complications but after no glasses or lenses need to be worn at all. Draw a labelled diagram to show refraction of light as it leaves a glass block into air. Draw a labelled diagram to show the path of light with an angle of incidence equal to the critical angle as it leaves a glass block into air. Draw a labelled diagram to show the path of light with an angle of incidence greater than the critical angle as it travels through a glass block in air.

28 Explain how to calculate the critical angle using Snell s law What are the two things that change in refraction? How is density related to the speed of light? When the critical angle is the angle of incidence, the light will be refracted along the edge of the block and so, the angle of refraction is 90 degrees. Sin 90 = 1. Sin c = the refractive index of the material the light is going into the refractive index of the material the light is coming from. Speed and direction. The greater the density of the material, the slower the light will travel and the more energy will be absorbed. How is total internal reflection used in optical fibres? Where are endoscopes used in diagnosis? Where are endoscopes used in treatment? Where is ultrasound used in diagnosis? Where is ultrasound used in treatment? A bundle of fibres is used. Light is sent along some of the fibres, at an angle greater than the critical angle of glass, from the light source and it travels along the fibres by total internal reflection as shown. The reflected image travels back to the eye along other fibres. Visual inspection of internal organs for example in colonoscopy. Biopsies can be taken and eye hole surgery performed. Scanning during pregnancy and to locate kidney stones, cysts etc in internal organs To break up kidney stones and in treating muscle problems. Topic 2 What are X-rays? What is the process where electrons are boiled off a cathode (filament) called? Why is a voltage needed across the cathode (filament) in a simple electron gun? Why is a high voltage (potential difference) needed between the cathode (-) and the anode (+)? Why is there a vacuum in an electron gun? What name is given to the beam of electrons in an electron gun? High energy electromagnetic waves. They are a type of ionising radiation. They have a high frequency and a short wavelength. Thermionic emission. To provide the ionisation energy to the electrons using the heating effect of current. To accelerate the electrons by repelling them away from the cathode and towards the anode. So there are no particles to get in the way. Electrons are accelerated straight across and their kinetic energy is not wasted. Cathode rays.