Force Interactions, Vectors and Free-body Diagrams
Represent contact and non-contact interactions, weight, resultants and equilibrium with vectors.
How to study for GCSE Physics
Move deliberately among physical models, diagrams, equations, units, graphs, experiments and evaluation; finish with the exact paper and practical structure named by your exam board.
Core concepts
Concept 1
A force is an interaction between objects and has magnitude and direction.
Exam cue: Choose the object, draw and label each external force, then combine with a stated sign convention.
Concept 2
A free-body diagram shows forces acting on one chosen object, not every force in the situation.
Exam cue: Keep interaction pairs on different objects and distinguish mass from weight.
Concept 3
Balanced forces produce zero resultant but do not imply the absence of forces.
Exam cue: Name the physical quantities, use consistent SI units and connect the model to observable evidence.
Targeted study blocks
Tier coverage
Foundation core with Higher-tier extensions
Higher tier includes the full DfE vector treatment; practise scale diagrams, resolution and equilibrium where marked.
Risk pitfalls and guardrails
Cancelling a Newton's-third-law pair on one object.
Guardrail: Do not memorise a formula pattern without quantities, units and conditions, and do not substitute Combined Science coverage for the full separate qualification.
Substituting into an equation before identifying the system, quantities and units.
Guardrail: Do not memorise a formula pattern without quantities, units and conditions, and do not substitute Combined Science coverage for the full separate qualification.
Using a Combined Science checklist or another board's paper allocation as the separate-Physics specification.
Guardrail: Check the live specification, practical section and assessment-series support materials before final revision or timed practice.
Memory anchors
Contact force
A force arising through physical contact between objects.
Non-contact force
A force mediated by a field without direct contact.
Free-body diagram
A vector diagram of external forces acting on one object.
Force Interactions, Vectors and Free-body Diagrams: method
Choose the object, draw and label each external force, then combine with a stated sign convention.
Force Interactions, Vectors and Free-body Diagrams: check
Keep interaction pairs on different objects and distinguish mass from weight.
Checkpoint rule
Do the check-up only after you can summarize each concept in one sentence and identify one dangerous pitfall from memory.
Knowledge Check (after reading)
Short check-up to confirm understanding of this module.
Check-up Questions
A book rests on a table. Which pair of forces belongs on a free-body diagram of the book?
A magnet attracts an iron nail without touching it. How should the interaction be classified?
Answer all questions to submit.
Next step personalized recommendations
Continue learning
Move forward only after this module is stable.
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