In this Grade 3 lesson from Science: A Closer Look, Chapter 6, students learn what a force is — a push or pull — and how forces can change an object's motion by making it start, stop, speed up, slow down, or change direction. Students also explore key concepts including balanced and unbalanced forces, gravity, weight, friction, and magnetism. An inquiry activity using a ramp and toy car helps students investigate how the amount of force applied affects how far an object travels.
Section 1
Forces Change Object Motion
A force is simply a push or a pull. When a force is applied to an object, it causes a change in the object's motion.
Forces can make an object:
Section 2
Magnets Attract and Repel Objects
Magnets create forces that can attract things made of certain metals like iron or repel other magnets without touching them. This magnetic force works through solids, liquids, and gases.
Section 3
Gravity Pulls Objects Toward Earth
Gravity is a pulling force between objects that keeps us on Earth. An object's weight measures how much gravity pulls on it. Objects with more mass experience stronger gravitational pull.
Section 4
Friction Slows Moving Objects
Friction occurs when objects rub against each other, creating a force that slows movement. Rough surfaces produce more friction than smooth ones. People can increase or decrease friction depending on their needs.
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Section 1
Forces Change Object Motion
A force is simply a push or a pull. When a force is applied to an object, it causes a change in the object's motion.
Forces can make an object:
Section 2
Magnets Attract and Repel Objects
Magnets create forces that can attract things made of certain metals like iron or repel other magnets without touching them. This magnetic force works through solids, liquids, and gases.
Section 3
Gravity Pulls Objects Toward Earth
Gravity is a pulling force between objects that keeps us on Earth. An object's weight measures how much gravity pulls on it. Objects with more mass experience stronger gravitational pull.
Section 4
Friction Slows Moving Objects
Friction occurs when objects rub against each other, creating a force that slows movement. Rough surfaces produce more friction than smooth ones. People can increase or decrease friction depending on their needs.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter