GCSE Physics Paper 1 is next: where to start (and what to skip)

Physics revision works differently from other GCSE revision. Biology has a clear arc: cells, then systems, then disease. Maths builds topic by topic. History has a narrative spine.

Physics Paper 1 doesn't work like that. Energy, electricity, the particle model, and atomic structure don't flow from one to the next — they're four distinct topics that happen to share the same exam paper. There's no natural revision order, which is why it's easy to spend three evenings on energy and realise you haven't touched circuits yet.

The other thing that trips people up: physics has more equations than the other sciences, and they interact. The kinetic energy equation uses mass and velocity. The power equations link to the circuit equations. Efficiency links back to energy. Getting comfortable with the equations — not just recognising them, but being able to rearrange them — is probably the single highest-leverage thing to do in the run-up.

The advice below works for GCSE Physics revision whether you're doing Triple Physics or Combined Science. The topic overlap is substantial, and the sequencing logic is the same.

This is the topic that pays the most marks and causes the most confusion — not because it's hard, but because the terminology is easy to muddle.

Circuits are one of the few areas of physics where the rules are completely consistent. Learn the rules once and they apply to every circuit question.

The earth wire — what it actually does

This is one of the most searched questions in the run-up to Physics Paper 1, and the answer is simpler than most revision notes make it sound.

The earth wire provides a low-resistance path to the ground. If a fault develops and the live wire touches the metal casing of an appliance, current flows through the earth wire rather than through the person touching the appliance. The large current causes the fuse to blow (or the circuit breaker to trip), cutting off the supply.

The earth wire doesn't carry current in normal operation. It's a safety measure, not a functional part of the circuit. That's the distinction the mark scheme is looking for. More on mains electricity safety here.

Series vs parallel — the quick reference

The key equations

All three boards examine these equations in Paper 1. Being able to rearrange them quickly matters for multi-step questions.

• V = IR (Ohm's law — voltage = current × resistance)
• P = IV (power = current × voltage)
• P = I²R (power = current squared × resistance)
• Q = It (charge = current × time)
• E = QV (energy = charge × voltage)

This is the single highest-leverage GCSE Physics revision activity. It separates a grade 5 from a grade 7 in physics more reliably than any specific topic. The equations themselves aren't difficult — it's the algebraic rearrangement under pressure that causes marks to drop.

The kinetic energy equation, worked through

The kinetic energy equation is Ek = ½mv².

Rearranging for velocity:

• Ek = ½mv²
• 2Ek = mv² (multiply both sides by 2)
• v² = 2Ek ÷ m (divide both sides by m)
• v = √(2Ek ÷ m) (square root both sides)

Rearranging for mass: From v² = 2Ek ÷ m, rearrange to m = 2Ek ÷ v².

The step students most often get wrong is forgetting to square root at the end when solving for v. The answer is v, not v². Annotating that final step is worth a mark.

We've written a full worked-example guide to rearranging the KE equation if you want to practice more variants.

The simple trick

Cover the quantity you're trying to find with your thumb. What's left is the right-hand side of your rearranged equation. It works for V = IR, P = IV, and most of the single-step physics equations. For two-step rearrangements (like the KE equation), write out each step on a separate line — it's slower, but it's where the marks are.

The AQA equation sheet is available on the AQA website (search "AQA GCSE Physics equation sheet 8463"). Know which equations are given to you and which you need to memorise — efficiency, density, and the wave equation are among those students sometimes assume are on the sheet but aren't.

Specific heat capacity and specific latent heat are the two calculation-heavy topics in this section.

Specific heat capacity (SHC): Q = mcΔT, where Q is energy transferred (joules), m is mass (kg), c is specific heat capacity (J/kg°C), and ΔT is the change in temperature.

The most common exam question asks students to calculate the energy needed to heat a specific mass of a material by a set number of degrees. Watch the units — temperature changes must be in °C or K (the change is the same either way), and mass must be in kg not grams.

Specific latent heat (SLH): Q = mL. This applies during a state change, when temperature stays constant while energy is being supplied. The mark point that gets dropped is explaining why temperature doesn't rise during a state change — because the energy breaks intermolecular bonds rather than increasing the kinetic energy of the particles.

OCR and Edexcel cover this material in their equivalent particle model sections. The equations and the conceptual explanation are the same across boards.

Both AQA and OCR include atomic structure in Paper 1 (typically Unit 4). Edexcel covers radioactivity in Paper 1 Topic 6. The content overlaps substantially across boards.

The key content: protons, neutrons, electrons; isotopes; the four types of nuclear decay (alpha, beta-minus, beta-plus, gamma); half-life calculations; nuclear equations using correct notation.

Half-life questions are almost always on the paper in some form. The definition to memorise: the half-life of a radioactive substance is the time it takes for half the nuclei in a sample to decay. Half-life calculation questions usually give you a graph or a table — you don't need to memorise a formula, just track the value halving.

Nuclear equations: make sure mass numbers and atomic numbers balance on both sides. Alpha decay reduces mass number by 4 and atomic number by 2. Beta-minus decay increases atomic number by 1 and keeps mass number the same.

Not every topic deserves equal attention in the run-up.

1. Electromagnetic waves in depth — wave properties basics are worth knowing, but detailed EM spectrum applications (gamma in medicine, microwaves in cooking) are lower mark-density than the energy and electricity topics.
2. Required practical details beyond the basics — know the method and the key sources of error, but don't memorise precise apparatus setups for every practical.
3. Magnetism (Triple only) — motor effect and electromagnetic induction are Triple Physics topics. If you're doing Combined Science, you can skip this entirely for Paper 1.
4. Detailed nuclear physics beyond half-life — fission, fusion, and nuclear reactors are Paper 2 topics for most boards. Don't spend Paper 1 revision time on them.

Pick one topic from the list above — whichever feels least solid — and spend 45 minutes on it. Not a marathon session; 45 minutes. Do a few practice questions, not just reading.

For past papers, Save My Exams has a strong collection of AQA Physics Paper 1 topic-by-topic questions with mark schemes, which is more useful at this stage than doing full timed papers. You can also work through PrepWise Physics quizzes topic by topic — they mark your answers as you type, so you see what's clicking before you finish a paper.

Tomorrow: start on whichever topic is next in the sequence. One day at a time is enough. GCSE Physics revision feels overwhelming because the course is fragmented — but sequenced sensibly, you have real time.