Lesson 1.1: Matter has mass and volume

Lesson Focus

Everything in the universe is made of matter. This lesson introduces the two fundamental properties that define matter: its mass and the space it occupies, or volume. You'll learn how to measure these essential quantities.

Learning Objectives

• Define what matter is and identify examples of it in the world around you.
• Understand mass as the amount of matter in an object and learn how to measure it.
• Discover how volume measures the space an object occupies and practice different ways to measure it.

The world is full of physical things, a phenomenon we call matter.

The cause is that all objects are made of "stuff" that has mass (an amount of material) and volume (takes up space).

This is made possible by atoms, the tiny building blocks of matter. Is air matter? Yes, because it has mass and volume.

Objects feel different because they contain varying amounts of matter.

We measure this property, called mass, using a balance.

The mechanism involves comparing an object to a standard unit, the kilogram (kg). A metal spoon has more mass than a plastic one because it contains more matter. More matter equals more mass.

When you feel an object's heaviness, you're experiencing its weight.

The cause is gravity pulling on the object's mass.

This is why your mass is constant everywhere, but your weight is less on the Moon. Weight is a force measured in Newtons (N). Remember: mass is the stuff, weight is the pull.

The space an object occupies is its volume.

For regularly shaped objects like a box, we can calculate volume with a formula: Volume = length × width × height.

We measure these dimensions and multiply them to get a result in cubic units like cm³. For example, a 2cm cube has a volume of 8 cm³.

How do we measure a rock's volume? We use displacement.

The mechanism is submerging the object in a measured amount of water.

The volume of the water that is pushed aside equals the object's volume. If the water level rises by 15 mL, the rock's volume is 15 cm³, because 1mL = 1cm³.