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An electromagnetic wave? Absorbed by a few cm of air?
Alpha Beta Gamma An electromagnetic wave? Absorbed by a few cm of air? Stopped only by very thick lead? A fast moving electron? A large, positively charged particle? Stopped by aluminium? Stopped by paper?
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Learning Objectives By the end of this lesson you should be able to… Describe the uses of different radioactive materials in the home and industry. Explain what is meant by the term ‘half-life’ of a radioactivity material. Describe why half-life is a useful tool when considering how to use radioactive materials.
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Learning Objectives By the end of this lesson you should... Describe the uses of different radioactive materials in the home and industry. Explain what is meant by the term ‘half-life’ of a radioactivity material. Describe why half-life is a useful tool when considering how to use radioactive materials. Half-Life This is 1kg of uranium. It contains 2.56 X 1024 atoms of Uranium. Partly because there are so many and partly because radioactive decay is a random process it is impossible to tell exactly when any one atom of uranium might decay!
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Learning Objectives By the end of this lesson you should... Describe the uses of different radioactive materials in the home and industry. Explain what is meant by the term ‘half-life’ of a radioactivity material. Describe why half-life is a useful tool when considering how to use radioactive materials. Half-Life Half-Life is a measure of how long it will take for half the atoms to have decayed (0.5kg). This gives us a wide margin of error and allows us to be much more precise!
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Half-Life The half-life for U235 is 703 Million years.
Learning Objectives By the end of this lesson you should... Describe the uses of different radioactive materials in the home and industry. Explain what is meant by the term ‘half-life’ of a radioactivity material. Describe why half-life is a useful tool when considering how to use radioactive materials. Half-Life The half-life for U235 is 703 Million years. This means after 703 million years 50% (half) the uranium will have decayed. After 1406 million years 75% quarters will have decayed. After 2109 million years 87.5% will have decayed.
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Modelling Half-Life Define the term ‘half-life’
Learning Objectives By the end of this lesson you should... Describe the uses of different radioactive materials in the home and industry. Explain what is meant by the term ‘half-life’ of a radioactivity material. Describe why half-life is a useful tool when considering how to use radioactive materials. Modelling Half-Life First use the data to plot a half-life curve. (no of flips x-axis). (no of skittles left on y-axis). Define the term ‘half-life’ Using your graph calculate the half-life (in flips) of the skittles. If I start with 5,000 skittles how many should I have left after 4 half-lives? If I have 2kg of Uranium what mass of uranium atoms will I be left with after 6 half lives.
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Modelling Half-Life Learning Objectives
By the end of this lesson you should... Describe the uses of different radioactive materials in the home and industry. Explain what is meant by the term ‘half-life’ of a radioactivity material. Describe why half-life is a useful tool when considering how to use radioactive materials. Modelling Half-Life
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Learning Objectives By the end of this lesson you should... Describe the uses of different radioactive materials in the home and industry. Explain what is meant by the term ‘half-life’ of a radioactivity material. Describe why half-life is a useful tool when considering how to use radioactive materials. Half-Life Half-life is an important consideration when using radiation. In medicine we sometimes inject small amounts of radiation and use a scanner to map its path showing blockages – what might be the best half-life?
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What do all these have in common?
Learning Objectives By the end of this lesson you should... Describe the uses of different radioactive materials in the home and industry. Explain what is meant by the term ‘half-life’ of a radioactivity material. Describe why half-life is a useful tool when considering how to use radioactive materials. What do all these have in common?
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Which type of radiation is used and why?
Learning Objectives By the end of this lesson you should... Describe the uses of different radioactive materials in the home and industry. Explain what is meant by the term ‘half-life’ of a radioactivity material. Describe why half-life is a useful tool when considering how to use radioactive materials. What the use How does it work Which type of radiation is used and why? What half life should the source have and why?
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More uses of tracers… Gamma source What the use How does it work
Learning Objectives By the end of this lesson you should... Describe the uses of different radioactive materials in the home and industry. Explain what is meant by the term ‘half-life’ of a radioactivity material. Describe why half-life is a useful tool when considering how to use radioactive materials. Gamma source What the use How does it work Which type of radiation is used and why? What half life should the source have and why?
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Which type of radiation is used and why?
Learning Objectives By the end of this lesson you should... Describe the uses of different radioactive materials in the home and industry. Explain what is meant by the term ‘half-life’ of a radioactivity material. Describe why half-life is a useful tool when considering how to use radioactive materials. What the use How does it work Which type of radiation is used and why? What half life should the source have and why?
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Which type of radiation is used and why?
Learning Objectives By the end of this lesson you should... Describe the uses of different radioactive materials in the home and industry. Explain what is meant by the term ‘half-life’ of a radioactivity material. Describe why half-life is a useful tool when considering how to use radioactive materials. What the use How does it work Which type of radiation is used and why? What half life should the source have and why?
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Radiotherapy Advantages Disadvantages Damage to neighbouring
Normal cells e.g. burns No surgery Kills cancer Radiation sickness e.g hair loss Accurate Risk of over exposure - staff and patients
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Which type of radiation is used and why?
Learning Objectives By the end of this lesson you should... Describe the uses of different radioactive materials in the home and industry. Explain what is meant by the term ‘half-life’ of a radioactivity material. Describe why half-life is a useful tool when considering how to use radioactive materials. Detector Rollers Paper Emitter What the use How does it work Which type of radiation is used and why? What half life should the source have and why?
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Which type of radiation is used and why?
Learning Objectives By the end of this lesson you should... Describe the uses of different radioactive materials in the home and industry. Explain what is meant by the term ‘half-life’ of a radioactivity material. Describe why half-life is a useful tool when considering how to use radioactive materials. What the use How does it work Which type of radiation is used and why? What half life should the source have and why? Different to one on sheet.
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