This definitions covers Key Definitions within Forces & Their Effects for GCSE Physics. Revise Forces & Their Effects in Forces for GCSE Physics with 28 exam-style questions and 11 flashcards. This topic shows up very often in GCSE exams, so students should be able to explain it clearly, not just recognise the term. It is section 7 of 13 in this topic. Make sure you can use the exact wording confidently, because definition marks are often lost through vague language.
📖 Key Definitions
Force: A push or pull that can change an object's speed, direction, or shape. Measured in Newtons (N). Force is a vector quantity.
Mass: The amount of matter in an object, measured in kilograms (kg). Mass is a scalar and does not change with location.
Weight: The gravitational force acting on an object. W = mg. Measured in Newtons (N). Weight varies with gravitational field strength.
Resultant force: The single force equivalent to all individual forces acting on an object combined. A non-zero resultant force causes acceleration.
Gravitational field strength (g): The force per unit mass at a point in a gravitational field. On Earth, g = 10 N/kg. On the Moon, g ≈ 1.6 N/kg.
Practice questions for Forces & Their Effects
What is a force?
Explain what is meant by the resultant force on an object.