In a nuclear reactor, plutonium-239 (94239Pu^{239}_{94}\text{Pu}94239Pu) nuclei can undergo induced fission to generate thermal power.
Describe what happens to a plutonium-239 nucleus immediately after it captures a thermal (slow-moving) neutron.
Explain the physical role of the moderator in maintaining this fission chain reaction.
Explain how the control rods are adjusted to prevent a runaway reaction and maintain a steady power output.
State the primary form of energy carried by the fission products (daughter nuclei and neutrons) immediately after the fission event.
The entire reactor core is enclosed in a thick concrete biological shield. Explain how this shield protects plant workers from the ionizing radiation produced inside.
22 exam-style questions on Edexcel IGCSE Physics Fission and fusion. Each one has a worked solution and a mark scheme showing where the marks go.