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Published byEmilio Dace Modified over 9 years ago
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P1 foundation
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House Insulation Methods How many can you name?
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savingspayback timedraught proofingcavity insulation cheapestdouble glazinghighest savingsloft insulation budgetcost6 years
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R M IR V UV X G Uses Dangers Long frequency Low wavelength High energy No dangers least most dangerous
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Long wavelength High frequency High energy Long wavelength Low frequency Low energy Radiowaves Microwaves Infra-red Visible Ultra-violet X-ray Gamma rays Uses Dangers Heating water in tissue – can burn Can burn skin over time Can damage eyes if too intense Burns skin, can cause skin cancer High doses can kill healthy cells Even low doses can kill healthy cells Transmits information over radios Cooking food and mobiles Remote controls and thermal imaging Seeing, optical fibres Sun beds, fluorescent tubing, security marking Taking pictures of bones Killing cancer cells, sterilising hospital equipment
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P1 higher
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Does it reduce conduction, convection or radiation?
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conductionconvectionradiationairinsulator kinetic energyenergy losswindowswallssavings particlestransferthicknessdenseheat
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Energy = mass x SHC x change in temp transferred Units Energy Mass Specific heat capacity Temperature J Kg J/Kg o C o C
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R M IR V UV X G Uses Dangers Long frequency Low wavelength High energy No dangers least most dangerous
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Long wavelength High frequency High energy Long wavelength Low frequency Low energy Radiowaves Microwaves Infra-red Visible Ultra-violet X-ray Gamma rays Uses Dangers Heating water in tissue – can burn Can burn skin over time Can damage eyes if too intense Burns skin, can cause skin cancer High doses can kill healthy cells Even low doses can kill healthy cells Transmits information over radios Cooking food and mobiles Remote controls and thermal imaging Seeing, optical fibres Sun beds, fluorescent tubing, security marking Taking pictures of bones Killing cancer cells, sterilising hospital equipment
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P2 foundation
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AlphaBetaGamma Most ionising PenetratingUsed to treat cancer sterilise equipment Stopped by aluminium Stopped by paper Used in smoke alarm Most penetratingUsed in paper mills Least ionising Least penetrating Reduced by lead/ concrete Ionising
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AlphaBetaGamma Most ionising Used in smoke alarms Least penetrating Stopped by paper Ionising Used in paper mills Penetrating Stopped by aluminium Least ionising Used to treat cancer / sterilise equipment Most penetrating Reduced by concrete or lead
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Uranium: alpha, long half life, very radioactive, needs cooling, buried in glass, not penetrating Iodine: highly penetrating, beta and gamma, short half life, very radioactive, need cooling, thick walled containers, metres of concrete, Mixed: short half life, slightly radioactive, land fill, deep underground, concrete, highly penetrating
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Meteor http://www.youtube.com/watch?v= OGbgt5bN-g0
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P2 higher
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AlphaBetaGamma
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AlphaBetaGamma Most ionising Used in smoke alarms Least penetrating Stopped by paper 2 protons and 2 neutrons Ionising Used in paper mills Penetrating Stopped by aluminium A fast moving electron Least ionising Used to treat cancer / sterilise equipment Most penetrating Reduced by concrete or lead An electromagnetic wave
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Uranium: alpha, long half life, very radioactive, needs cooling, buried in glass, not penetrating Iodine: highly penetrating, beta and gamma, short half life, very radioactive, need cooling, thick walled containers, metres of concrete, Mixed: short half life, slightly radioactive, land fill, deep underground, concrete, highly penetrating
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Red shift and big bang http://www.youtube.com/watch?v= U-OUP_mXMCw
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Red shift and big bang We know the universe is expanding because of the Doppler effect. You may have noticed that when an ambulance or police car goes past, its siren is high-pitched as it comes towards you, then becomes low-pitched as it goes away. This effect, where there is a change in frequency and wavelength, is called the Doppler effect and it doesn't only happen with sound. We can see it happening with light when we look at distant stars. The light is being stretched towards the red end of the spectrum because the object is moving away from us, just as it was with the police car. Evidence for this is shown by the location of these black lines in the spectrum of our Sun and in other stars. The black lines are where different elements such as helium absorb light. They are shifted towards the red end of the spectrum because of the Doppler effect. But be careful, just because things moving away from us are shifted towards the red end of the spectrum, doesn't mean they necessarily look red, they just have a longer wavelength.
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