This definitions covers Key Definitions within Newton's Laws of Motion for GCSE Physics. Revise Newton's Laws of Motion in Forces for GCSE Physics with 13 exam-style questions and 15 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 9 of 15 in this topic. Make sure you can use the exact wording confidently, because definition marks are often lost through vague language.
Topic position
Section 9 of 15
Practice
13 questions
Recall
15 flashcards
📖 Key Definitions
Newton's First Law: An object remains at rest or moves at constant velocity unless a resultant force acts on it.
Newton's Second Law: The acceleration of an object is directly proportional to the resultant force and inversely proportional to its mass. F = ma.
Newton's Third Law: For every action there is an equal and opposite reaction — forces act on different objects simultaneously.
Inertia: The resistance of an object to a change in its motion. Greater mass = greater inertia.
Resultant force: The single force that has the same effect as all the individual forces acting on an object combined.