Forces and Friction What are Forces? Lesson 1

Force A force is a push or pull on an object to make it move. push

Moving object A moving object will travel in a straight line if it is not touched.

Gravity Gravity is a force that pulls things down.

Lesson 2 How Do Magnets Work?

Magnet A magnet’s force can move something without touching it.

More Magnets A magnets force can attract objects through air, water and some solids.

The poles of a magnet are at its ends. Magnets have Magnets Again The poles of a magnet are at its ends. Magnets have a north and south pole.

The force of a magnet is strongest at the poles and weakest in the middle.

Opposite poles attract, or pull together. North South South North

Poles that are alike repel each other, or push each other away. South and south or North and north will repel each other.

A magnet is used to make a compass. The magnet always points north

How Can We Measure Motion? Lesson 3 How Can We Measure Motion?

Weight, friction, and distance, affect the force needed to move objects

Motion is when something moves.

It takes less force to move something light than something heavy.

It takes less force to move something on a smooth surface than on a rough surface

It takes less force to move something a short distance than a long distance.