Three Dimensional (3D) Shapes

 

LESSON – 3D SHAPES

TOPIC

• Introduction

• Meaning and Properties of Three Dimensional Shape

• Lesson Evaluation

 

INTRODUCTION – 2D AND 3D SHAPES 

Three dimensional shapes are objects or shapes that three dimensions such as length, width, and height.

Three dimensional shapes are known as 3D shapes.

While two dimensional shapes have just two dimensions such as length and width.

Two dimensional shapes are also known as 2D shapes.

 

The properties of a three dimensional shapes are,

1. Faces

2. Edges

3. Vertices

 

TYPES OF THREE DIMENSIONAL SHAPES

The following shapes are the basic three dimensional shapes we see around us,

1. Cube

2. Cuboid (Rectangular prism)

3. Triangular prism

4. Sphere

5. Cone

6. Cylinder

7. Pyramid

 

CUBE

A cube is a solid three dimensional shape which has 6 square faces.

 

 

Examples of cube are ice cube, cube square, dice, etc.

The cube has the following properties,

• 8 vertices (corners)

• 12 edges

• 6 faces

 

CUBOID

A cuboid is a solid three dimensional shape which has 6 rectangular faces or 4 rectangular faces and 2 square faces.

Six rectangular faces

 

Four rectangular faces with two square faces

Examples of cuboid are the lunch box, bricks, books, carton, cupboard, fridge, etc.

 

It is also called a rectangular prism.

The faces of the cuboid are a rectangle in shape.

The cuboid has the following properties,

• 8 vertices (corners)

• 12 edges

• 6 f aces

 

TRIANGULAR PRISM 

A triangular prism is a solid three dimensional shape which has 5 faces (2 triangles and 3 rectangles).

 

 

Examples of triangular prism are triangular roofs, camping tents, and chocolate candy bars.

 

The triangular prism has the following properties,

• 6 vertices

• 9 edges

• 5 faces

 

SPHERE 

A sphere is a three dimensional round shaped object with just one face.

 

 

Examples of sphere ball, moon, sun, eyeball, orange, etc.

 

The sphere has the following properties,

• No vertex

• No edges

• 1 curved face

 

CONE 

A cone is a three dimensional object or solid with a circular base and has a single vertex.

 

 

Examples of cone are hat, Ice cream cone, funnel, megaphone, christmas tree, traffic cone, etc.

The cone has the following properties,

• 1 vertex

• 1 edge

• 1 flat face – circle

• 1 curved face

 

CYLINDER 

A cylinder is defined as a three dimensional shapes with 2 circular bases connected by a curved surface.

 

 

Examples of cylinder pipes, cans, tanks, battery, gas cylinder, fire extinguisher, etc.

The cylinder has the following properties,

• No vertex

• 2 edges

• 2 flat faces – circles

• 1 curved face

 

PYRAMID 

A pyramid is also a three dimensional shape with a square base and four triangular faces.

 

 

Examples of pyramid are roof of a building, Egyptian pyramid, groundnut pyramid, etc.

 

There are different types of pyramid depending on their based.

We have the triangular, square, quadrilateral base but the most commonly used is the square pyramid.

The pyramid has the following properties,

• 5 vertices

• 8 edges

• 5 faces

 

LESSON EVALUATION 

Answer 5 questions including number 6.

1. explain the meaning of 3 dimensional shapes.

2. differentiate between 2D and 3D shapes.

3. identify and state the properties of 3 dimensional shapes.

4. state the uses of three dimensional shapes.

5. apply 3 dimensional shapes in real life situations.

 

6. state the properties of the following shapes,

• Cube

• Cuboid

• Triangular prism

• Cone

• Sphere

• Pyramid

• Cylinder