12 equations. Each page has 10 real-life ramped questions with full FIFA solutions. Every equation is given on the equation sheet in the exam.
Key: C+S = Combined and Separate | S only = Separate Physics only | HT = Higher tier only
- Weight: W = mg (C+S)
- Work done: W = Fs (C+S)
- Force on a spring: F = ke (C+S)
- Moments: M = Fd (S only)
- Pressure: p = F/A (S only)
- Pressure in a liquid: p = hρg (S only, HT)
- Distance, speed and time: s = vt (C+S)
- Acceleration: a = Δv/t (C+S)
- Resultant force: F = ma (C+S)
- Momentum: p = mv (C+S, HT)
- Uniform acceleration: v² − u² = 2as (C+S)
- Force and momentum change: F = mΔv/Δt (S only, HT)
Key definitions
Write your answer on paper first, then tap Show answer. Learn the key words – definition questions are quick marks in the exam.
1. What is the difference between a scalar and a vector quantity? Give an example of each. (C+S)
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A scalar has magnitude (size) only, e.g. speed, distance, mass. A vector has magnitude and direction, e.g. velocity, displacement, force.
2. What is the difference between a contact force and a non-contact force? (C+S)
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A contact force acts only when objects are physically touching, e.g. friction, air resistance, tension. A non-contact force acts when objects are physically separated, e.g. gravitational, electrostatic and magnetic forces.
3. What is weight? How is it different from mass? (C+S)
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Weight is the force acting on an object due to gravity, measured in newtons (N). Mass is the amount of matter in an object, measured in kg. Mass is the same everywhere; weight depends on the gravitational field strength.
4. What is a resultant force? (C+S)
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A single force that has the same effect as all the original forces acting together.
5. What is meant by work done? What is 1 joule? (C+S)
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Work is done when a force causes an object to move through a distance; work done = energy transferred. 1 joule of work is done when a force of 1 newton moves an object 1 metre (1 J = 1 N m).
6. What is the difference between elastic and inelastic deformation? (C+S)
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Elastic deformation: the object returns to its original shape and length when the forces are removed. Inelastic deformation: it does not return to its original shape and length.
7. What is the limit of proportionality? (C+S)
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The point beyond which the extension of a spring is no longer directly proportional to the force applied.
8. What is the moment of a force? (S only)
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The turning effect of a force. Moment = force × perpendicular distance from the pivot to the line of action of the force.
9. What is the difference between speed and velocity? (C+S)
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Velocity is speed in a given direction. Speed is a scalar; velocity is a vector.
10. What is acceleration? (C+S)
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The rate of change of velocity (change in velocity ÷ time taken). Unit: m/s².
11. State Newton’s first law. (C+S)
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If the resultant force on an object is zero, a stationary object stays stationary, and a moving object carries on moving at the same speed in the same direction (constant velocity).
12. State Newton’s second law. (C+S)
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The acceleration of an object is directly proportional to the resultant force acting on it, and inversely proportional to its mass (F = ma).
13. State Newton’s third law. (C+S)
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Whenever two objects interact, the forces they exert on each other are equal in size and opposite in direction.
14. What is inertia? (C+S, HT)
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The tendency of an object to continue in its state of rest or of uniform motion (same speed in the same direction).
15. What is terminal velocity? (C+S)
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The maximum constant velocity of a falling object, reached when the resistive force (e.g. air resistance) equals its weight, so the resultant force is zero.
16. What is the stopping distance of a vehicle? (C+S)
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Stopping distance = thinking distance + braking distance. Thinking distance is how far the car travels during the driver’s reaction time; braking distance is how far it travels once the brakes are applied.
17. State the law of conservation of momentum. (C+S, HT)
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In a closed system, the total momentum before an event (such as a collision or explosion) is equal to the total momentum after the event.
18. What is pressure? (S only)
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The force acting at right angles (normal) to a surface, per unit area. Unit: pascal (Pa), where 1 Pa = 1 N/m².
