Lesson 2 Density Density is a property of

Lesson 2: Density

Density is a property of matter that shows a relationship between mass and volume. It measures the amount of matter in a certain space.

less dense than Cotton Ball Iron Ball An object or substance with a low density will have less mass than a more dense object with the same volume.

Discovery Education Video: Density: The Relationship Between Mass and Volume Density is a measure of how much stuff there is (mass) in a certain amount of space (volume). Equal sizes (volumes) of different substances will have different weights (masses). Changing the physical property of size causes an object that normally sinks to float.

An object’s density can be calculated if we know it’s mass and volume. Density is measured using the unit grams per cubic centimeter (g/cc).

To calculate density, we divide the object’s mass by the object’s volume

A golf ball has a mass of 45 grams and a volume of 40 cubic centimeters Density = Mass ÷ Volume Density = 45 ÷ 40 Density = 1. 13 g/cc

Water has a density of 1 g/cc. An object with a density less than 1 g/cc will float, but an object with a density more than 1 g/cc will sink.

Buoyancy is the ability of an object to float in water.

Key Questions: 1) What does density measure? How is it related to mass and volume? 2) How can we measure the density of an object? 3) What makes an object buoyant in water? How does this relate to the object’s density?