Your GCSE physics equation sheet is more than a list to memorise. Used well, it becomes a quick decision tool for homework, revision, and exam questions. This guide explains common GCSE physics formulas by topic, shows what each symbol means, gives the expected units, and includes short worked examples you can revisit before tests. The aim is simple: help you recognise which equation fits a question, use it with confidence, and avoid the small errors that cost marks.
Overview
A strong GCSE physics revision routine is not just about knowing equations. It is about knowing when to use them, what each variable means, and how to keep units consistent. Many students lose marks not because the topic is impossible, but because they mix up symbols, forget to convert units, or choose an equation that does not match the question.
Think of this article as a GCSE physics equation sheet explained by topic. It works as a checklist you can return to before homework, class tests, mocks, and final exams. Even if your exam board provides an equation sheet, you still need to understand the relationships behind the formulas. If you are not sure how to approach longer written problems, it also helps to pair this guide with How to Solve Physics Word Problems Step by Step.
Before looking at topics, keep this universal checklist in mind:
- Read the question twice and underline the quantities given.
- Write down the known values with units.
- Identify what the question asks for.
- Choose an equation containing the known quantities and the unknown.
- Rearrange carefully if needed.
- Convert units before substituting values.
- Check whether your answer is reasonable.
One more habit matters a lot: build your own small annotated equation sheet as you revise. Instead of copying formulas only, add a short note beside each one such as “use when speed changes over time” or “works for resistors in series.” That turns physics formulas into usable tools rather than isolated facts.
Checklist by scenario
This section groups GCSE physics revision equations by topic so you can quickly match a question to the right formula family.
1. Motion and kinematics
Use these equations for speed, distance, time, and acceleration questions.
- Speed = distance / time
- Acceleration = change in velocity / time
Symbols and units
- speed, velocity: m/s
- distance, displacement: m
- time: s
- acceleration: m/s²
Mini-example: A car travels 150 m in 10 s. Its speed is 150 / 10 = 15 m/s.
Use this checklist when you see:
- “average speed”
- distance-time data
- velocity changing over time
- graphs involving motion
Quick reminder: speed is scalar, velocity includes direction. In many GCSE questions, that distinction matters when interpreting wording.
2. Forces and Newton's laws
These equations appear in mechanics, motion, and interaction questions.
- Force = mass × acceleration
- Weight = mass × gravitational field strength
- Momentum = mass × velocity
Symbols and units
- force: N
- mass: kg
- acceleration: m/s²
- weight: N
- gravitational field strength: N/kg
- momentum: kg m/s
Mini-example: A 2 kg object accelerates at 3 m/s². The force is 2 × 3 = 6 N.
Use this checklist when you see:
- pushing, pulling, braking, lifting
- objects speeding up or slowing down
- weight on Earth or another planet
- collisions and changes in momentum
Common clue: if a question gives mass in grams, convert to kilograms before using force, weight, or momentum equations.
3. Work, energy, and power
This set is central to many GCSE physics tutorials because it links mechanics, electricity, and efficiency.
- Work done = force × distance
- Kinetic energy = 0.5 × mass × speed²
- Gravitational potential energy = mass × gravitational field strength × height
- Power = energy transferred / time
- Efficiency = useful output / total input
Symbols and units
- work done, energy: J
- force: N
- distance, height: m
- power: W
- time: s
Mini-example: A student lifts a 5 kg bag by 2 m. Taking gravitational field strength as 9.8 N/kg or the classroom value requested by the question, the gain in gravitational potential energy is mgh = 5 × 9.8 × 2 = 98 J.
Use this checklist when you see:
- lifting, moving, pushing
- energy stores changing
- machines, motors, appliances
- “how much useful energy” or “how efficient”
If you want extra practice, Work, Energy, and Power Problems with Step-by-Step Answers is a useful companion.
4. Electricity: charge, current, voltage, resistance, and power
Electricity questions often look harder than they are because there are several linked formulas. The key is to decide whether the question is about current flow, energy, or circuit combination.
- Charge = current × time
- Potential difference = current × resistance (Ohm's law form)
- Power = current × potential difference
- Energy transferred = charge × potential difference
Symbols and units
- charge: C
- current: A
- time: s
- potential difference: V
- resistance: Ω
- power: W
- energy: J
Mini-example: A 6 V lamp carries a current of 0.5 A. Its power is P = IV = 0.5 × 6 = 3 W.
Use this checklist when you see:
- batteries, lamps, heaters, motors
- resistance calculations
- electrical power ratings
- energy transferred in a circuit
For circuit combinations and setup patterns, see Series and Parallel Circuits Explained with Formula Sheet and Examples.
5. Density, pressure, and moments
These formulas often appear in mixed-topic papers because they test both concept knowledge and unit control.
- Density = mass / volume
- Pressure = force / area
- Moment = force × perpendicular distance
Symbols and units
- density: kg/m³
- mass: kg
- volume: m³
- pressure: Pa
- area: m²
- moment: N m
Mini-example: A force of 20 N acts 0.3 m from a pivot. The moment is 20 × 0.3 = 6 N m.
Use this checklist when you see:
- floating and sinking
- solids and fluids under force
- balanced beams and levers
Questions in this area often involve awkward units such as cm³ or cm², so careful conversion matters.
6. Waves
Waves equations are compact, but the ideas behind them need clear definitions.
- Wave speed = frequency × wavelength
- Period = 1 / frequency
Symbols and units
- wave speed: m/s
- frequency: Hz
- wavelength: m
- period: s
Mini-example: A wave has frequency 5 Hz and wavelength 2 m. Its speed is 5 × 2 = 10 m/s.
Use this checklist when you see:
- electromagnetic waves
- sound waves
- water waves
- oscillations and cycles
Students often confuse frequency and period, so always ask: is the question about “cycles per second” or “time for one cycle”?
7. Thermal physics
Thermal questions may use equations about energy transfer and changes in temperature.
- Energy for heating = mass × specific heat capacity × temperature change
Symbols and units
- energy: J
- mass: kg
- specific heat capacity: J/kg°C or J/kgK
- temperature change: °C or K difference
Mini-example: Heating 2 kg of a material with specific heat capacity 400 J/kg°C by 5°C needs E = 2 × 400 × 5 = 4000 J.
Use this checklist when you see:
- heating blocks or liquids
- temperature rise
- required energy input
Be careful to use temperature change, not the final temperature by itself.
8. Radioactivity and half-life
Not every exam requires a formal equation here, but students still need a method.
Checklist for half-life questions:
- Identify the starting count, mass, or activity.
- Count how many half-lives have passed.
- Halve the value once for each half-life.
- Keep track of units such as Bq, g, or counts per minute.
Mini-example: If activity starts at 80 Bq and two half-lives pass, it falls to 40 Bq, then 20 Bq.
For this topic, a repeated method is often more useful than one memorised line.
What to double-check
Before finalising any answer, run through this short inspection list. It saves marks.
- Units: Are all values in standard units? Convert cm to m, g to kg, minutes to seconds if needed. For extra support, see Physics Unit Conversions Guide: SI Units, Prefixes, and Dimensional Analysis.
- Correct variable: Did you use distance or displacement, speed or velocity, mass or weight?
- Equation choice: Does the formula include the quantity the question actually asks for?
- Rearrangement: If you had to change the subject, did you keep brackets and powers correct?
- Powers and squares: In kinetic energy, speed is squared. Missing that changes the answer a lot.
- Rounding: Match the data in the question and avoid over-rounding too early.
- Sense check: Is your answer physically reasonable? A walking speed of 300 m/s should make you stop and review.
It also helps to label answers with words, not just numbers. Writing “15 m/s” is better than writing “15” alone. Examiners cannot reward a complete calculation if the final answer has no meaningful unit.
Common mistakes
Most GCSE physics equation mistakes are predictable. That is good news, because predictable mistakes can be prevented.
- Using values without converting units. A time given in minutes must usually become seconds.
- Mixing up mass and weight. Mass is measured in kg; weight is a force measured in N.
- Forgetting that area is in square units. If dimensions are in cm, convert properly before using pressure formulas.
- Confusing energy and power. Energy is measured in joules; power is the rate of transfer measured in watts.
- Using the final temperature instead of temperature change. In heating equations, the difference matters.
- Dropping the square in speed². This is common in kinetic energy questions.
- Choosing a familiar formula instead of the right one. Students often reach for the first equation they remember.
- Ignoring the wording of the question. “Calculate,” “explain,” and “compare” ask for different types of response.
A useful exam habit is to annotate the question margin with a tiny plan: “knowns, unknown, equation, convert, solve.” That five-step routine creates consistency under time pressure.
If you want a broader reference set across mechanics, energy, waves, and electricity, bookmark Physics Equations Sheet by Topic: Kinematics, Forces, Energy, Waves, and Electricity. For motion-specific applications, Projectile Motion Calculator Guide: Range, Time, Height, and Common Mistakes can also sharpen equation selection, even if projectile motion sits slightly beyond some GCSE uses.
When to revisit
This is the kind of topic you should return to regularly, not once. A physics equation sheet only becomes useful through repeated use in slightly different situations.
Revisit this guide when:
- you start a new physics topic and need the core formulas in one place
- you are making flashcards or a personal revision sheet
- you notice repeated mistakes in homework or mock papers
- your class begins timed exam practice
- you need a quick reset the week before an assessment
A practical routine for the final weeks before an exam:
- Split your revision by topic: motion, forces, energy, electricity, waves, thermal physics.
- For each topic, write the key equation from memory.
- Add the symbol meanings and units underneath.
- Complete one mini-example without notes.
- Check mistakes and correct your sheet.
- Repeat two days later with a different question.
This turns passive reading into active physics exam prep. It is especially helpful if you feel that GCSE physics formulas look familiar but still seem hard to apply.
Finally, remember that an equation sheet is a map, not the whole journey. The real exam skill is matching a physical situation to the right relationship. If you build that habit now, your revision becomes quicker, calmer, and more reliable each time you return to it.
