The difference between prisms & pyramids.

“It’s all about how you slice it!”

Pyramids and prisms are specific kinds of polyhedra.

The word polyhedra is the plural form of polyhedron.

A polygon is a 2-dimensional shape.

A polyhedron is a 3-dimensional shape.

Presto! A triangular prism!

Presto! A triangular pyramid!

Presto! A square prism!

Presto! A square pyramid!

A prism is made of congruent shapes.

A pyramid is made of similar shapes that get smaller and

smaller.

If you know the names of common polygons, then naming a prism or pyramid will be easy

for you.

Look at the polygon on the bottom of the shape.

This polygon is a rectangle.

This shape is a rectangular prism.

This shape is a rectangular pyramid.

This is a pentagon.

This is a pentagonal prism.

This is a pentagonal pyramid.

This is an octagon.

This is an octagonal prism.

This is an octagonal pyramid.

If you know the common polygons and if you know the

difference between a prism and a pyramid, naming these shapes is

easy.

The only unique name that you have to remember is the “cube.”

A cube is a specific kind of rectangular prism.

A rectangular prism that has 6 congruent faces is called a cube.

A rectangular prism that has 6 congruent faces is called a cube.

A rectangular prism that has 6 congruent faces is called a cube.

A rectangular prism that has 6 congruent faces is called a cube.

A rectangular prism that has 6 congruent faces is called a cube.

A rectangular prism that has 6 congruent faces is called a cube.

• A sphere is the set of all points in space that are the same distance from a point, the center of the sphere.

• A hemisphere is created when a sphere is cut in half.

Surface Area of a Sphere

• Surface area = 4 π (radius)2

• S = 4 π r2

C Radius

Find the Surface Area of a Sphere• Find the surface area of the sphere. Round your

answer to the nearest whole number.a.

The radius is 8 in.

24S r24 (8)

8 in. 2804644 in

Find the Surface Area of a Sphere• Find the surface area of the sphere. Round your

answer to the nearest whole number.b.

The radius is 5 cm.

24S r24 (5)

10 cm.2314254 cm

Volume of a Sphere

• Volume = 343r

343

V rradiusC

Find the Volume of a Sphere• Find the volume of the sphere. Round your answer to the

nearest whole number.

a.

32 (3.14)3

343

V r

34 (2)3

4 (8)3

323

334 .ft

2 ft.

Find the Volume of a Sphere• Find the volume of the hemisphere. Round your answer to

the nearest whole number.

b. A hemisphere has half the volumeof a sphere.

31 42 3

V r

31 4 (5)2 3

2503

3262 .in

a 5 in.

Find the Volume of a Sphere• Find the volume of the sphere. Round your answer to the

nearest whole number.

a.34

3V r

34 (6)3

4 (216)3

2883905 .in

6 in.

AssignmentWorksheet 24 and 26 in packet