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Electricity · Chapter 5: Nuclear power

Year 11 Science · About 17 minutes with activities · Turn your sound on

Chapter 5 · Nuclear power
One tiny neutronboils tonnes of water?
Fusion: nuclei joinlost mass → energy
Fission: it splits2 or 3 neutrons fly out
Chain reactioneach fission → more fissions
Runaway!×3 every generation
Control rodsabsorb neutrons
Moderator (water)slows neutrons down
Fuel: uranium-235splits when hit
Steady: 1 → 1 → 1each fission triggers one more
Nuclear→Heat→Kinetic→Electrical
Both rows balancetop: mass · bottom: atomic

Chapter 5 recap

  • Fusion: nuclei combine to form a larger nucleus (the Sun, hydrogen bombs, fusion reactors). Fission: a large nucleus such as U-235 splits when hit by a neutron.
  • Each fission releases 2–3 neutrons → chain reaction. Control rods absorb neutrons to slow or stop it; the moderator slows neutrons down.
  • Heat boils water → steam turns turbines → generator. Mass and atomic numbers must balance. Radioactive waste is cooled, sealed and isolated.
  • Next: Chapter 6 · Renewable electricity

How can one tiny neutron boil water in a power station?

Chapter 5 · About 17 minutes · sound on

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