This document contains a lesson on spheres that includes: 1) Objectives about applying the volume and surface area formulas for spheres and developing problem-solving skills 2) Examples of calculating the surface area and volume of various spheres and hemispheres 3) Word problems involving spheres that require using the volume formula 4) An assignment to complete problems #4-22 on page 842 of the homework that are even numbers.

1. 12.6 Spheres April 12, 2011
Bellwork
Get a cone and a pyramid from the back table.
Find the volume of each.
Put bellwork in homework bin.
HW pg. 842 #4­22 evens 1

2. 12.6 Spheres April 12, 2011
12‐6 Surface Area of a Sphere
Objectives:
1. You will be able to apply the volume formula for a sphere.
2. You will be able to apply 3D visual thinking skills.
3. You will be able to develop reading comprehension & problem‐solving skills.
SA = 4πr2
Find the surface area of a sphere with a diameter of 14.2 cm
HW pg. 842 #4­22 evens 2

3. 12.6 Spheres April 12, 2011
Find the surface area of the hemisphere at the left
if the diameter is 12 in.
HW pg. 842 #4­22 evens 3

4. 12.6 Spheres April 12, 2011
Volume of a Sphere
4 3
V= πr
3
Find the volume of the sphere below:
18 in
HW pg. 842 #4­22 evens 4

5. 12.6 Spheres April 12, 2011
What is the volume of a basketball with a
circumference of 12π?
What is the volume of the snow cone?
3 in
7 in
HW pg. 842 #4­22 evens 5

6. 12.6 Spheres April 12, 2011
How much clay would be
needed to create the bowl at the right if
the bowl is .5 in thick and the distance
from the center of the bowl to the edge is
in 10 in?
10
HW pg. 842 #4­22 evens 6

7. 12.6 Spheres April 12, 2011
A beach ball has a diameter of 20 inches. If the blue section
were removed from the beach ball, what would the remaining
volume be? (assume all sections are equal in size)
HW pg. 842 #4­22 evens 7

8. 12.6 Spheres April 12, 2011
Homework:
12.6 pg. 842 #4­22 evens
HW pg. 842 #4­22 evens 8