Force and Motion II: Key Terms (Form 5 SPM Physics)

Terms and definitions

• Resultant force, The single force that has the same effect as two or more forces acting together on an object.
• Resolution of forces, The process of splitting a single force into two components, usually perpendicular to each other.
• Forces in equilibrium, The condition in which the resultant of all forces acting on an object is zero, so it stays at rest or moves with constant velocity.
• Free body diagram, A diagram that shows all the forces acting on a single object, drawn as arrows from the object.
• Inclined plane, A flat surface set at an angle to the horizontal, on which an object's weight can be resolved into components along and perpendicular to the surface.
• Elasticity, The property of a material that allows it to return to its original shape and size after the force deforming it is removed.
• Hooke's law, Within the elastic limit, the extension of a spring is directly proportional to the force applied to it.
• Spring constant, The force needed to produce unit extension in a spring, a measure of its stiffness; measured in newtons per metre (N m⁻¹).
• Elastic limit, The maximum force or extension beyond which a spring or material no longer returns to its original length.
• Limit of proportionality, The point up to which the extension of a spring stays directly proportional to the applied force.
• Elastic potential energy, The energy stored in a spring or elastic object when it is stretched or compressed.
• Pascal's principle, Pressure applied to an enclosed fluid is transmitted equally and undiminished throughout the fluid in all directions. (related term from another chapter)
• Hydraulic system, A system that uses Pascal's principle to multiply force by transmitting pressure through an enclosed liquid, as in a hydraulic jack. (related term from another chapter)
• Archimedes' principle, An object wholly or partly immersed in a fluid experiences an upward buoyant force equal to the weight of the fluid it displaces. (related term from another chapter)
• Buoyant force, The upward force exerted by a fluid on an object immersed in it. (related term from another chapter)

Content standards these terms come from

• 1.1 Resultant Force
• 1.2 Resolution of Forces
• 1.3 Forces in Equilibrium
• 1.4 Elasticity

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 II resources

• Chapter overview: Force and Motion II
• 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)