1. Density
•Identify objects of different density (3)
•Describe how to calculate density of a regular shaped objects
(4)
•Explain how to calculate the density of irregular shaped objects
(5)
•Use density investigations to identify unknown solids (6)
•Design density investigations to identify unknown solids (7)
aq
QUESTION:
What does the word eureka mean?
3. The exclamation 'Eureka!' is
famously attributed to the
ancient Greek scholar
Archimedes
He reportedly proclaimed
"Eureka!" when he stepped into
a bath and noticed that the
water level
He suddenly understood that the volume
of water displaced must be equal to the
volume of the part of his body he had
submerged
4. King Hiero II of Syracuse gave
some pure gold to his goldsmith
to make him a crown
He suspects the goldsmith has
stolen some of the gold and
replaced it with a cheaper metal
like copper or lead
Q) How can Hiero be sure his new
crown is pure gold?
5. Regular shape
20 cm
10 cm
40 cm
Density =
Mass
Volume
Volume = 10 x 20 x 40 = 8000 cm3
Mass = 154.4 kg
Density =
154400
= 154400 g
= 19.30 g/cm3
8000
6. 1. Find the mass of your object
2. Fill the eureka can up to the spout. Allow
the excess to drain out into your
beaker.
Throw the excess water away
3. Place your object gently into the
eureka can and collect the
displaced water in your beaker
4. Use a measuring cylinder
to find the volume of
the displaced water.
Repeat for as many different objects as possible
50.00
0
1
2
3
4
5
6
7
8
9
10
ml
9. 0
1
2
3
4
5
6
7
8
9
10
ml
1. Find an object which
floats
2. Compare the mass of the object to the volume of
the water displaced.
What do you notice?
HINT: What is the
density of water?
10. Easy – 1 Mark Medium – 2 Marks Hard – 3 Marks
Write the equation to
calculate density
An object has a mass
40,000 kg and volume of 5
cubic metres. What is its
density
Remember units
A stone of mass 30 grams is
placed in a measuring
cylinder of water. The water
level increases from 50cm3
to 60 cm3
. What is the
density of the stone?
Rearrange this equation for
mass.
An object has a volume of 3
cubic metres and a density
of 6000 kilograms per cubic
metre. What is its mass?
Remember units
The density of air is
1.3kg/m3
. What mass of air
is contained in a room
measuring 2.5m x 4m x
10.5m? How does this
compare with your mass?
11. Easy – 1 Mark Medium – 2 Marks Hard – 3 Marks
Mass / Volume 8000kg/cm3
3g/cm3
Density x Volume 18000kg/cm3
137kg/m3
