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Published byGwenda Anderson Modified over 8 years ago
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There is good evidence for the Big Bang from red shifted spectra and cosmic background radiation. There is uncertainty about the effect of gravity in the future because of uncertainties in measurements, in particular in the total mass of the Universe.
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Answering 6 mark questions For 5−6 marks: answer describes correctly evidence for the Big Bang and reasons for uncertainty about the future of the Universe. All the information given is relevant, clear and organised in a structured and coherent format. Specialist terms are used appropriately. Few errors, if any, in grammar, punctuation and spelling. For 3−4 marks: answer describes correctly some evidence for the Big Bang and uncertainties about the future. For the most part the information is relevant and presented in a structured format. Specialist terms used for the most part appropriately. There may be occasional errors in grammar, punctuation and spelling.
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C/W 13 th October 2011 Recap - Electromagnetic radiation Keywords: electromagnetic spectrum photon transmit transparent absorb translucent vacuum Objectives: Must – Describe what the electromagnetic spectrum is. Should – Describe how electromagnetic waves behave. Could – Electromagnetic waves of different frequency carry different amounts of energy.
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homework
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Electromagnetic Spectrum Radio Micro Infra-Red Light Ultra-Violet X rays Gamma Wavelength ( ) increases Can you think of a phrase that would help you remember this order? Gate X Usually Lets In Most Radiation High frequency Short wavelength High energy Most penetrating High frequency Short wavelength High energy Most penetrating Low frequency Long wavelength Low energy Least penetrating Low frequency Long wavelength Low energy Least penetrating x
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Gamma waves – the highest energy
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X-rays
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Ultra-violet waves
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Visible light
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Infra red
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microwaves
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Radio waves
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Starter – emag wave catch phrase.
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C/W 18 th October 2011 Radiation intensity Keywords: intensity, photon, energy transfer. Objectives: Must – Understand how energy is transferred by electromagnetic waves. Should – Understand what radiation intensity is. Could – Understand what things effect intensity
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We saw last week we can think of light as little packets of energy called photons.......
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As you get further away from a light source it gets less intense as the light spreads over a larger space......... Intensity = the energy transferred per second per meter J/m 2 s
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Lets see this!!!! Black box
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Text book questions 3-4 page 239 Thank you
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C/W 18 th October 2011 Ionisation Keywords: ionising radiation Objectives: Must – Understand what ionising radiation is Should – understand how ionisation occurs Could – Understand that ionisation can course damage to living cells.
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Ionisation
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Role play......... Describe in 4 steps what is happening.... Use the words, electron, ionisation, high energy photon 1.Before the photon gets there 2.As it arrives 3.After it has collided
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Ionisation happens with high energy photons...... Ie x-rays or gamma rays.....you cant just add the energy of lots of infra red rays for example.
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Why is ionisation harmful? If this happens in your cells it can damage your DNA. This can cause cancers.
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