Why does an uncontrolled chain reaction in a large piece of uranium cause an explosion?
Each fission releases far more energy than a controlled one does
A very large amount of energy is released in a very short time
The uranium nuclei fuse together as well as splitting apart
The gamma rays emitted push the pieces of uranium apart quickly
40 exam-style questions on AQA GCSE Physics 4.4 Nuclear fission and fusion, covering 4.4.1 Nuclear fission and 4.4.2 Nuclear fusion. Each one has a worked solution and a mark scheme showing where the marks go.