density

Question 1

Density is

Answer 1

the mass per unit volume of a material:

Question 2

it is measured in

Answer 2

kg/m3 or

g/m3

g/cm3

Question 3

density symbol

Answer 3

p

Question 4

Objects made from low density materials typically have

Answer 4

a low mass

Question 5

volume symbol and unit

Answer 5

V m3

Question 6

Density is related to mass and volume by the following equation:

Answer 6

Question 7

The units of density depend on what units are used for mass and volume:

Answer 7

If the mass is measured in g and volume in cm3, then the density will be in g/cm3.

If the mass is measured in kg and volume in m3, then the density will be in kg/m3.

Question 8

Answer 8

Question 9

The main thing to remember is that density is

Answer 9

mass per unit volume.

Question 11

density is greater when the object is a

and smaller when is a

the exception is …because

so ice… in water

Answer 11

solid

liquid

water as solid is less dense than when liquid

floats

Question 12

Floating

Answer 12

an object will float in a liquid if the average density of that object is less than the density of the liquid it is placed in.

Question 13

Answer 13

Question 14

Measuring Density

To measure the density of an object, we must measure its mass and volume and then use the following equation:

Answer 14

Question 15

The mass of an object can be measured quite simply by placing it on a
You ought to state that you will the balance before using it.

Answer 15

top pan balance or mass balance

‘zero’

Question 16

measurements In the case of a liquid,

Answer 16

the liquid must be placed in a container, the mass of which should be measured both when it is empty and when it contains the liquid:
The mass of the liquid will be the difference between the two values.

Question 17

The volume can be determined in a couple of ways depending if

Answer 17

it is a regular shape or not

Question 18

regular shapes

Answer 18

Regular shapes (e.g. cubes, spheres, cylinders):

The width (and length) can be measured using a ruler or a pair of digital calipers.

To make the measurements accurate, several measurements should be taken between different faces or points on the circumference, and an average taken.

The volume can then be calculated using an appropriate equation:

Question 19

Irregular shapes:The volume can be found using a Eureka can:

Answer 19

The volume can be found using a Eureka can:

Fill the Eureka can with water.

Place an empty measuring cylinder below its spout.

Now carefully lower the object into the Eureka can (use a piece of string, perhaps).

Measure the volume of displaced water in the measuring cylinder.

Alternatively, the object can be placed in a measuring cylinder containing a known volume of liquid, and the change in volume then measured.

Once the mass and volume of the shape is known, its density can be calculated.

Question 20

Answer 20