In some nuclear power reactors, boron is dissolved in the liquid moderator as a 'chemical shim' to control the rate of fission.
During a power-up maneuver, the operator decreases the concentration of dissolved boron in the moderator.
Explain how decreasing the concentration of boron in the moderator increases the rate of the nuclear chain reaction.
94 exam-style questions on Edexcel GCSE Physics 6.5 Uses and dangers of radioactivity, covering 6.5.1 Uses of radioactivity, 6.5.2 Dangers of ionising radiation and precautions, 6.5.3 Half-life and radiation dangers, 6.5.4 Safety precautions for radiation exposure, and 6.5.5 Contamination and irradiation. Each one has a worked solution and a mark scheme showing where the marks go.