Page 499 - Canadian BC Science 9

As you can see in Diagram A, the volume of a regularly shaped solid object can be measured directly.
A
4cm×4cm×4cm=64cm3 5cm×6cm×3cm=90cm3
The volume of a liquid can be measured directly, as shown in Diagram B. Make sure you measure to the bottom of the meniscus, the slight curve where the liquid touches the sides of the container. To measure accurately, make sure your eye is at the same level as the bottom of the meniscus.
4 cm
3 cm 4 cm
4 cm
Measuring the volume of a regularly shaped solid
5 cm
6 cm
B
100
graduated cylinder
90
line where
80 liquid touches
read here 70 glass
The units used to measure the volume of liquids are called capacity units. The basic unit of volume for liquids is the litre (L). In this course, you also measure volume using millilitres (mL). Recall that 1 L 􏰀 1000 mL. You have probably seen capacity in litres and millilitres printed on juice, milk, and soft drink containers.
Cubic units and capacity units are interchangeable. For example:
1cm3 􏰀1mL 1 dm3 􏰀 1 L
1 m3 􏰀 1 kL
60 meniscus 50
C
Measuring the volume of an irregularly shaped solid
volume of object 􏰀 volume of water with object 􏰂 original volume of water 􏰀 85 mL 􏰂 60 mL
1. Recordthevolumeofthe liquid.
2. Carefullylowertheobjectinto the cylinder containing the liquid. Record the volume again.
3. Thevolumeoftheobjectis equal to the difference between the two volumes of the liquid. The equation below the photograph shows you how to calculate this.
Measuring the volume of a liquid
The volume of an irregularly shaped solid object, however, must be measured indirectly asshowninDiagramC.Thisisdoneby determining the volume of a liquid it will displace.
40 30
liquid
123
􏰀 25 mL
too high
too low
Science Skill 7 • MHR 481