2. What we are going to achieve today Find out about a chain reaction Understand how a nuclear power plant works Know what they do with the nuclear waste Know how we are protected from radiation on the Earth Know how spacemen protect themselves in space
4. A Chain of Chain Reaction in a Nuclear powers station A Neutron is released into a large number of Uranium atoms. when the Neutron hits a Uranium atom .................( finish the sentence)
5. When an atom splits into two smaller atoms energy is released and ....... (finish the sentence)
13. Read the paper and answer the questions Nuclear Waste Disposal – Questions Why does radioactive material emit less radiation as time goes on? Why is it important that the storage site should have a deep (low) water table? Imagine that a small amount of radioactive waste were to get into the drinking water supply. Which do you think would be most dangerous to health: an emitter of alpha, beta or gamma rays? Why? Name the disease that radiation exposure increases our chances of getting. A large proportion (often about 30%) of radioactive waste from nuclear power stations consists of plutonium-239, atomic number 94 (which is virtually non-existent in nature). It is unstable and breaks up (decays), emitting alpha particles. Write the symbol for the other product of this decay, an isotope of uranium. (Answer: uranium-235, atomic number 92) Current plans are to bury 70,000 tons of waste in Yucca Mountain, filling the available space by about 2036. Let us assume that 20,000 tons of this waste consists of plutonium-239, which has a half-life of 24,000 years. This means that if you take a handful of plutonium-239, you can predict that half of its atoms will have decayed within 24,000 years (although you can’t predict which ones). How much plutonium-239 will be left after 48,000 years? Think of as many ways as you can for radioactive waste, after it has been buried, to find its way up to the surface where it could harm people and other life. (Possible answers: volcanic eruption (last one in the area was 10,000 years ago, and history shows the area is becoming less volcanically active with time), earthquakes (waste containers will be designed to withstand ‘worst case’ earthquakes, and earthquakes release most of their destructive force at the surface), raising of water table, climate change leading to increased rainfall with water reaching the waste containers below and corroding them (made of extremely corrosion-resistant alloy, and past climate change suggests that rainfall is not likely to increase much in the next 10,000 years), drilling/mining by future humans who are unaware of the repository’s presence (unlikely that future inhabitants will lose knowledge of the repository while still retaining the technology to drill/mine that deep, and anyway there are no resources worth mining). Based on US Department of Energy calculations, an individual living at Yucca Mountain 10,000 years in the future will receive an annual radiation dose less than what he or she would receive from eating a single banana a year. Have a guess as to why bananas might be slightly radioactive. (Answer: bananas contain potassium which has a small naturally-occurring radioactive component. Dose: 0.1 microsieverts.)
14. Protection from radiation The Earth magnetic field protects us from the suns radiation. This can be seen as the aurora (Northern lights) Find out how people are shielded in space from radiation.
15. Styles from a hat You must write down an explanation of what you have learnt today using a style from the hat. You may be as creative as you like, Each pair will have a style, you can discuss what you will write in your book and then both write it in your book
16. Styles Pantomime Western Romance Soap Opera Sci-Fi Period drama Crime/ murder mystery Horror Action adventure Comedy
