1. Density, Mass, Volume
Sunday, 07 April 2019

2. What is density?
Density is defined by dividing a materials mass by its volume.
𝐷𝑒𝑛𝑠𝑖𝑡𝑦= 𝑚𝑎𝑠𝑠 𝑣𝑜𝑙𝑢𝑚𝑒
It was discovered by Archimedes and is key to analysing the different ways in which some materials react in various fluids.
For example
Some woods float in water because they have a lower density.
Whilst some metals will sink in water because the metal has a much higher density.

3. Example
Find the density for each of the following materials
Mass 350g , Volume 5 cm3
Mass 1400g , Volume 25 cm3
Zinc which has a mass of 56.8 g and a volume of 8 cm3

4. M D V 𝐷𝑒𝑛𝑠𝑖𝑡𝑦= 𝑀𝑎𝑠𝑠 𝑉𝑜𝑙𝑢𝑚𝑒 𝐷𝑒𝑛𝑠𝑖𝑡𝑦×𝑉𝑜𝑙𝑢𝑚𝑒=𝑀𝑎𝑠𝑠 𝑉𝑜𝑙𝑢𝑚𝑒= 𝑀𝑎𝑠𝑠 𝐷𝑒𝑛𝑠𝑖𝑡𝑦
Example
Find the mass for a material with density 6.5 g/cm3 which has a volume 3.5 cm3

5. Example
Find the mass for a material with density 18.2 g/cm3 which has a volume 7 cm3

6. Example
A piece of Gold has a density of g/cm3 and a mass of 250 g.
What is the volume of this gold?

7. 𝐷𝑒𝑛𝑠𝑖𝑡𝑦= 𝑀𝑎𝑠𝑠 𝑉𝑜𝑙𝑢𝑚𝑒
Find the density for each of the following masses with stated volumes
a) An object with mass 300 g which has a volume of 12 cm3.
b) An object with mass 13.8 g which has a volume of 3 cm3.
c) An object with mass 1.24 kg which has a volume of 155 cm3.

8. 𝐷𝑒𝑛𝑠𝑖𝑡𝑦×𝑉𝑜𝑙𝑢𝑚𝑒=𝑀𝑎𝑠𝑠
Find the Masses for each of the following Volumes with stated densities.
a) An object with Density 1.8 g/cm3 and volume 5 cm3
b) An object with Density 2.7 g/cm3 and volume 9 cm3
c) An object with Density 16.5 g/cm3 and volume 3.1 cm3