ThinkRankForce
A force is a push or pull that can change an object’s motion, direction, or shape. Contact forces and non-contact forces act in different ways, and the effect of a force depends on its strength, direction, and the object involved. Force is described through observable changes, not just effort or movement.
Learning Objectives
- •Explain effects of force
- •Explain contact and non-contact
- •Explain forces interact
Key Concepts
Effects of force
A force can start, stop, speed up, slow down, change direction, or deform an object.
Contact and non-contact
Muscular and frictional forces require contact, while magnetic, electrostatic, and gravitational forces can act at a distance.
Forces interact
Forces arise from interactions between objects and can have different directions and strengths at the same time.
Terminology
Historical Insight
Pushing a cart
The cart’s acceleration depends on the applied push, mass, wheel friction, and direction.
Magnet and paper clip
Magnetic attraction acts without direct contact, demonstrating a non-contact force.
Quick Check
What can a force change?
Give one contact and one non-contact force.
Why is direction important when describing a force?
How to use this lesson
Read the overview first, then explain the main idea in your own words before checking the key concepts. Use the quick-check questions without looking at the answer. For examination preparation, verify dates, definitions, and syllabus requirements against your official textbook and school or examination-board guidance.