Force and Motion I: Key Terms (Form 4 SPM Physics)

Terms and definitions

• Displacement, The distance moved in a stated direction from a starting point; a vector quantity measured in metres (m).
• Velocity, The rate of change of displacement with time; a vector quantity, measured in metres per second (m s⁻¹).
• Acceleration, The rate of change of velocity with time; a vector quantity measured in metres per second squared (m s⁻²).
• Free fall, The motion of an object falling under the action of gravity alone, with no air resistance.
• Gravitational acceleration, The acceleration of an object in free fall due to gravity, about 9.81 m s⁻² near the Earth's surface.
• Inertia, The tendency of an object to resist any change to its state of rest or uniform motion.
• Mass, The amount of matter in an object; a scalar quantity measured in kilograms (kg), and a measure of its inertia.
• Momentum, The product of the mass and velocity of an object; a vector quantity (momentum = mass × velocity), measured in kg m s⁻¹.
• Principle of conservation of momentum, The principle that the total momentum of a system remains constant in the absence of an external force, so total momentum before a collision equals total momentum after.
• Force, A push or pull acting on an object that can change its shape, or its state of rest or motion; a vector quantity measured in newtons (N).
• Impulse, The product of a force and the time for which it acts, equal to the change in momentum it produces; measured in newton seconds (N s).
• Impulsive force, The large force acting over a very short time during a collision or explosion (impulsive force = change in momentum ÷ time).
• Weight, The gravitational force acting on an object's mass; a vector quantity (weight = mass × gravitational field strength), measured in newtons (N).
• Scalar quantity, A physical quantity that has magnitude only, with no direction, such as distance, speed and mass. (related term from another chapter)
• Vector quantity, A physical quantity that has both magnitude and direction, such as displacement, velocity and force. (related term from another chapter)

Content standards these terms come from

• 2.1 Linear Motion
• 2.2 Linear Motion Graphs
• 2.3 Free Fall Motion
• 2.4 Inertia
• 2.5 Momentum
• 2.6 Force
• 2.7 Impulse and Impulsive Force
• 2.8 Weight

How to learn them

1. Cover the definition, say it aloud, then check the unit.
2. Pair each term with a formula or experiment from the chapter.
3. Write the Malay term alongside the English one, SPM papers are bilingual.

More Force and Motion I resources

• Chapter overview: Force and Motion I
• Revision Notes
• Common Mistakes
• Practice Questions
• Paper 2 Answering Guide
• Paper 3 Guide
• Calculation practice sets

Source: DSKP KSSM Physics Form 4 and 5 (Versi English), Sijil Pelajaran Malaysia: Format Pentaksiran mulai 2021, Fizik (4531) (Bahagian Pembangunan Kurikulum (BPK), KPM)