Forces
A force is a push or pull. Forces can change the speed, direction, or shape of an object. Common forces include gravity, friction, and applied force.
What You Need to Know
Key Concept Diagram
All forces are either pushes or pulls
Gravity is the force that pulls objects towards Earth's centre
Friction is a force between two surfaces that opposes motion
When forces are balanced, an object remains still or moves at constant speed
Key Vocabulary
Force
A push or pull that can change an object's motion, speed, or shape
Gravity
The force of attraction between objects; on Earth, it pulls things downward
Friction
A force that opposes motion between two surfaces in contact
Balanced forces
Forces acting on an object that are equal and opposite, resulting in no change in motion
Knowledge Check
Select the correct answer for each question. Click "Check Answer" to see if you are right.
Question 1
What type of force is gravity?
Question 2
You push a book across a table and it slows down. What force is slowing it?
Question 3
A book sitting still on a desk has balanced forces acting on it. This means:
Key Concepts Summary
- ●All forces are either pushes or pulls
- ●Gravity is the force that pulls objects towards Earth's centre
- ●Friction is a force between two surfaces that opposes motion
- ●When forces are balanced, an object remains still or moves at constant speed