Chapter 10 Surface Area & Volume

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Transcript Chapter 10 Surface Area & Volume

Section 10 – 3
Surface Area Of
Prisms & Cylinders
Objective:
To find the surface area of a prism
To find the surface area of a cylinder
Prism:
A polyhedron with exactly two
congruent, parallel faces
Base:
Congruent, parallel faces
Lateral Faces:
Faces that ARE NOT bases
Height of Prism:
The length of the altitude that
joins the two bases
We Name a Prism by the Shape of its Bases
Lateral Area:
The sum of the areas of the lateral faces
Surface Area:
The sum of the lateral area and the area of the
two bases
Example 1 Finding Surface
Area of a Prism
A) Use a net to find the lateral and surface
area of the rectangular prism below.
B) Use a net to find the lateral and surface area
of the triangular prism below.
C) Use a net to find the lateral and surface area
of the cube below.
Theorem 10 – 1
Lateral & Surface Area of Prisms
L.A. = ph
S.A. = L.A. + 2B
Example 2
Using Formulas to
Find Surface Area
A) Use formulas to find the lateral area and
surface area of the prism.
B) Use formulas to find the lateral area and
surface area of the prism.
C) Find the surface area of a 10 cm high prism
with triangular bases having 18 cm edges.
Round to the nearest whole number.
HOMEWORK
Textbook Page 531 – 532; #1 – 7 All
Section 10 – 3
Continued…
Objective:
To find the surface area of a cylinder
Cylinder:
Has two congruent, parallel circle bases
Base:
Congruent, parallel circle faces
Height of Cylinder:
The length of the altitude that
joins the two bases
Lateral Area:
The curved surface between the two bases
(when unrolled – it is a rectangle)
Surface Area:
The sum of the lateral area and the area of the
two bases
Theorem 10 – 2
Lateral & Surface Area of Cylinders
L.A. = ch
Or 2πrh
S.A. = L.A. + 2B
𝟐
Or 2πrh +2π𝒓
Example 3
A)
Finding Surface
Area of a Cylinder
The radius of the base of a cylinder is 4 in.
and its height is 6 in. Find the lateral and
surface area of the cylinder in terms of π.
B)
Find the lateral and surface area of a
cylinder with height 10 cm and radius 10
cm in terms of π.
C)
The radius of the base of a cylinder is 6 ft,
and its height is 9 ft. Find its lateral and
surface area in terms of π.
Example 4
Real-World
Connection
A) The drums of the roller below are
cylinders of length 3.5 ft. The diameter of the
drum is 4.2 ft. What area does the large drum
cover in one full turn? Round your answers to
the nearest square foot.
B) A company sells cornmeal and barley in
cylindrical containers. The diameter of the base
of the 6 in. high cornmeal container is 4 in. The
diameter of the base of the 4 in. high barley
container is 6 in. Which container has the
greater surface area?
10 – 3 Ditto; #1 – 15 Odd