25 15 One model of a nuclear reaction involves a neutron hitting a uranium nucleus.
uranium nucleus neutron
release of energy
(a) Describe how the model could be used to show a chain reaction. You may draw on the diagram. ................................................................................................................................................... ................................................................................................................................................... .............................................................................................................................................. [2] (b) Describe how, in a nuclear reactor, the chain reaction is kept under control. ................................................................................................................................................... .............................................................................................................................................. [1]
Š OCR 2015
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