This annotated GCSE Physics equation sheet brings the main required formulas into one clean reference for revision, homework, and exam practice. It is designed for grade 9-10 students who need to choose equations quickly and connect symbols with units. The sheet groups the formulas into three color-coded sections and ten focused cards so students can revise without clutter.
Key Facts
- Speed is calculated using , where is speed, is distance, and is time.
- Acceleration is calculated using , and uniformly accelerated motion can use .
- Force, mass, and acceleration are linked by , so a larger resultant force gives a larger acceleration for the same mass.
- Weight is calculated using , and gravitational potential energy is calculated using .
- Work done and energy transferred are calculated using , while kinetic energy is .
- Electrical power can be calculated using or , and charge flow is calculated using .
- Waves follow , where is wave speed, is frequency, and is wavelength.
- Density is calculated using , and pressure is calculated using .
Vocabulary
- Resultant force
- The single overall force acting on an object after all forces have been combined.
- Energy transfer
- The movement of energy from one store or pathway to another, measured in joules.
- Power
- The rate at which energy is transferred or work is done, calculated using .
- Potential difference
- The energy transferred per unit charge between two points in a circuit, measured in volts.
- Frequency
- The number of complete waves passing a point each second, measured in hertz.
- Density
- The mass per unit volume of a material, calculated using .
Common Mistakes to Avoid
- Using mass instead of weight is wrong because mass is measured in kilograms while weight is a force measured in newtons using .
- Forgetting to square the speed in gives an answer that is too small and does not follow the kinetic energy relationship.
- Mixing up current and charge is wrong because is the rate of charge flow while is the total charge, linked by .
- Using centimetres instead of metres without converting can make answers wrong because GCSE equations usually require SI units such as , , , and .
- Choosing an equation by matching letters only is risky because the same symbol can mean different quantities, so always check the quantity, unit, and context.
Practice Questions
- 1 A car travels in . Calculate its speed using .
- 2 A object accelerates at . Calculate the resultant force using .
- 3 A heater transfers of energy in . Calculate its power using .
- 4 Explain why checking units can help you choose between , , and in an electricity question.
Understanding GCSE Physics Equation Sheet Annotated
An equation is a model of a physical situation, not a trick for producing a number. Start by deciding what is changing and what causes that change. A moving object can have a constant speed even when a force acts on it, provided the forces balance.
Acceleration happens when there is a resultant force. This idea helps with unfamiliar questions about cars, lifts, parachutes, or objects on slopes. Draw a simple force diagram before calculating.
Include weight, contact forces, friction, air resistance, thrust, and tension where appropriate. The direction of the resultant force tells you the direction of acceleration.
Mass is measured in kilograms, while weight is a force measured in newtons. Mixing these two quantities is a common source of lost marks.
Motion calculations need careful reading because several words sound similar. Distance is the total path travelled, while displacement includes direction. Speed has no direction, while velocity does.
Acceleration means a change in velocity, so an object can accelerate while slowing down if its velocity is changing in the opposite direction. On a distance time graph, the gradient represents speed. On a velocity time graph, the gradient represents acceleration and the area under the graph represents displacement.
These graph links are useful because they show where equations come from. For a braking vehicle, think about both the driver response distance and the braking distance. A heavier vehicle, a faster starting speed, or poor road conditions can change the outcome.
Energy questions become clearer when you trace where energy starts and where it ends. A falling object transfers energy from its gravitational store to its kinetic store. In real situations, some energy is transferred to thermal energy because of air resistance or friction.
Energy is conserved overall, but not all of it remains useful for the intended purpose. Work done measures energy transferred when a force moves an object through a distance in the force direction. Power measures how quickly energy is transferred.
This matters in appliances, motors, kettles, and charging devices. In electricity problems, current is the rate of charge flow.
A large current for a short time can transfer the same charge as a smaller current for a longer time. Check whether a question gives time in seconds, minutes, or hours before choosing units.
Waves, density, and pressure connect equations to material properties and everyday design. Wave speed depends on the medium. Frequency is set by the source and stays the same when a wave enters a new medium, while wavelength can change.
Density explains why the same volume of steel has more mass than the same volume of wood. Pressure explains why sharp blades cut well and why wide tyres reduce sinking on soft ground. In every calculation, write down the known values with units first.
Convert units before substituting numbers, especially centimetres to metres, grams to kilograms, and minutes to seconds. Rearrange an equation before inserting values when the required quantity is not already the subject. Finally, check whether the answer has a sensible size and the correct unit.