184 Chapter 7 Length and Length-Related Parameters
EXAMPLE 7.2 Determine the exterior volume of the object shown in Figure 7.16.
For this example, we will use the buoyancy effect to measure the exterior volume of the
object shown. We will consider two procedures. First, we obtain a large container that can
accommodate the object. We will then fill the container completely to its rim with water and
place the container inside a dry, empty tub. We next submerge the object with the unknown
volume into the container until its top surface is just below the surface of the water. This will
displace some volume of water, which is equal to the volume of the object. The water that
overflowed and was collected in the tub can then be poured into a graduated cylinder to mea-
sure the volume of the object. This procedure is shown in Figure 7.17.Object
■Figure 7.16
The object in Example 7.2.Object
Tub
Overflowed water
from the tubGraduated
■Figure 7.17 cylinder
Using a displaced volume of
water to measure the volume of
the given object.Object
■Figure 7.18
Using apparent weight (actual
weight minus the buoyancy
force) to determine the volume
of a given object.The second procedure makes direct use of the buoyancy force. We first suspend the object
in air from a spring scale to obtain its weight. We then place the object, still suspended from the
spring, into a container filled with water. Next, we record the apparent weight of the object. The
difference between the actual weight of the object and the apparent weight of the object in water
is the buoyancy force. Knowing the magnitude of the buoyancy force and using Equation (7.7),
we can then determine the volume of the object. This procedure is depicted in Figure 7.18.Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s).圀圀圀⸀夀䄀娀䐀䄀一倀刀䔀匀匀⸀䌀伀䴀圀圀圀⸀夀䄀娀䐀䄀一倀刀䔀匀匀⸀䌀伀䴀