1. Mass, Density and Flotation
Chapter 40

2. Mass Density and Flotation
The mass of an object is the amount of matter in it. The unit of mass is the kilogram(kg) or gram(g).
The mass of an object is found by using an electronic balance

3. Density The density of a substance is the mass of 1cm3 of it
The unit of density is the g/cm3 (gram per cm3)

4. To Find the density of a solid or liquid you need to know two things:
The mass in grams (g)- use an electronic balance.
The volume of it in centimeters cubed(cm3)

5. To find the volume of an object you can use an overflow can

6. Once you have the mass and the volume you can find the density using the density formula.
Density = Mass(g)
Volume(cm3)

7. Flotation The density of water is 1g/cm.3
An object sinks if its density is greater than the density of the liquid it is in.
All the cubes are the same size. Their sides are of length 2 cm.

8. Question What is the volume of each cube?
Do you notice anything about the density of the cubes that floated?
Can you come to any conclusions?
An object floats if its density is less than the density of the liquid it is in.