How energy is released when mass changes, E = mc², nuclear fission and chain reactions, nuclear fusion, and the arguments for and against the use of nuclear energy, including safety and disposal.
6 narrated scenes. Press play, listen and read along — the points appear as they are explained. Use ‹ Prev / Next › or the scene bar to jump to any scene.
A single gram of matter, completely converted to energy, would release about as much energy as burning tens of thousands of litres of petrol. This is the power of the nucleus.
Narration uses your device’s built-in voice. No sound? Switch to “Captions only” — the captions advance on their own.
Start a chain reaction and control it with control rods.
Copy these into your notebook in your own words — that is how they stick.
Products have slightly less mass than the reactants.
Energy released = mass lost × (speed of light)².
A neutron splits a U-235 nucleus: two nuclei, 2–3 neutrons, energy; chain reaction.
Control rods absorb neutrons; moderator slows them; coolant removes heat.
Light nuclei join at very high temperature; powers the Sun.
High yield, low CO₂, reliable.
Waste, accidents, cost, hazards in the Caribbean.
Time, distance, shielding, monitoring.
3 quick games on this lesson. Earn XP and badges as you play — your best score for each game is saved. Games are for practice and do not change your exam readiness. More games in the Physics Arcade.
8 items modelled on real CSEC Paper 1 questions. Choose one answer for each, then check. Aim for 80% or better. Work each item on paper first.
Write full answers, then reveal the mark scheme and tick the points you earned (16 marks in total). Show all your working — method marks count. Your answers are saved on this device.
Question 1 [16 marks]
A nuclear power station uses uranium-235. A student prepares to debate whether a nuclear power station should be built in the Caribbean. Take c = 3.0 × 10⁸ m/s.
(a) (a) State what is meant by nuclear fission. [2]
(b) (b) Describe how a chain reaction occurs. [3]
(c) (c) State the function of the control rods and the moderator in a reactor. [2]
(d) (d) In one reaction the mass lost is 3.0 × 10⁻²⁹ kg. Calculate the energy released. [3]
(e) (e) State two arguments for and two against building a nuclear reactor in the Caribbean. [4]
(f) (f) State two safety precautions for handling a radioactive source in a laboratory. [2]
Find these in your own past-paper booklets for extra timed practice. Items above are written in the style of these papers; any adapted from a specific question say so.