Volume
of regular
composite
shapes
By now, students are familiar
with the concept that “volume” is
a measure of the amount of
space an object occupies
If we wanted to know the area on the ground
that this box was covering.
Area of a
rectangle
A=LXW
W L
If we wanted to know the amount of space that
that this box was occupying.
Volume of
a box
V=LXWXH H
W L
Volume of a box
(be sure to make a note of this)
V = (L)(W)(H)
H
W L
Which gives the area
So the volume formula is just the appropriate area
formula multiplied by the third dimension
V = area of the end X third dimension
From now on, to calculate volume of regular shapes
1. Find the area of the end
2. Multiply by the length
Imagine a cup that is the shape of a cylinder
The bottom is a circle
A r 2
The third dimension is
the height
h
Therefore:
V r h 2
r
Volume of a cylinder
(be sure to make a note of this)
Stop here
See sheet
Volume of a sphere
r
How much air is in a basketball?