# 3D Geometry Shapes – Definition, Properties, Types

Exploring the World of 3D Geometric Shapes

When we think of geometry, we often conjure up images of two-dimensional shapes like circles, triangles, and squares. These shapes are fundamental and easy to visualize, but there’s a whole other dimension waiting to be explored: the world of three-dimensional geometric shapes. In this article, we will dive into the fascinating realm of 3D geometric shapes, understanding their properties, and appreciating their significance in various aspects of our lives.

## What Are 3D Geometric Shapes?

3D geometric shapes, also known as three-dimensional shapes, are objects that exist in three dimensions: length, width, and height. Unlike their 2D counterparts, these shapes have depth, which adds an extra dimension to their complexity. 3D shapes are all around us, from simple ones like cubes and spheres to more intricate shapes such as dodecahedrons and tori.

## Examples of Three Dimensional Shapes

Three-dimensional shapes, or 3D shapes, are solid objects that exist in three dimensions, with length, width, and height. Common examples include the cube, spheres, cylinders , cones and pyramids. Here are 3d figures. ### Real-life Examples of Three Dimensional Shapes

Three-dimensional shapes, also known as 3D shapes or solid shapes, are prevalent in the physical world around us. Here are some real-life examples of 3D shapes:

1. Cube: A dice or a Rubik’s Cube are examples of cubes, with all sides being equal squares.
2. Sphere: Planets like Earth and objects like marbles are spherical, having a round, three-dimensional shape.
3. Cylinder: Soda cans, soup cans, and water bottles are typically cylindrical in shape, with circular bases and a curved surface.
4. Cone: Ice cream cones, traffic cones, and party hats are common cone shapes, with a circular base tapering to a point.
5. Pyramid: The Great Pyramid of Giza in Egypt is a well-known pyramid shape, with a polygonal base and triangular faces converging at a single vertex. ### Attributes of Three Dimensional Shapes

Three-dimensional shapes, also known as 3D shapes or solid shapes, possess several key attributes that define their characteristics and distinguish them from two-dimensional shapes. Here are the essential attributes of 3D shapes: 1. Dimensions: 3D shapes exist in three dimensions—length, width, and height. Unlike 2D shapes that are flat, 3D shapes have depth, making them fully solid objects.
2. Faces: Each 3D shape is composed of one or more flat surfaces, known as faces. These faces can be of different shapes, such as squares, rectangles, triangles, or other polygons. The number of faces varies for different 3D shapes.
3. Edges: Edges are the straight-line segments where the faces of a 3D shape meet. Edges define the boundaries and intersections between the faces. The number of edges can vary, depending on the shape.
4. Vertices: Vertices (singular: vertex) are the points where three or more edges intersect. Vertices are like corners or points in 3D space and determine the shape’s overall structure. The number of vertices also varies among different 3D shapes.

## Types of 3D Shapes

Three-dimensional shapes, often referred to as 3D shapes or solid shapes, come in various types, each with its unique characteristics. Here are some common types of 3D shapes:

1. Polyhedra: Polyhedra are solid shapes with flat faces and straight edges. Some well-known polyhedra include:
• Cube: All faces are identical squares.
• Tetrahedron: Four triangular faces.
• Octahedron: Eight triangular faces.
• Dodecahedron: Twelve regular pentagonal faces.
• Icosahedron: Twenty equilateral triangular faces.
2. Prisms: Prisms have two parallel and congruent polygonal bases connected by rectangular or parallelogram faces. Common prisms include:
• Rectangular Prism: Rectangular bases and rectangular faces.
• Triangular Prism: Triangular bases and rectangular faces.
• Pentagonal Prism: Pentagonal bases and rectangular faces.
3. Pyramids: Pyramids have a polygonal base and triangular faces that meet at a single vertex. Examples include:
• Square Pyramid: Square base with triangular faces.
• Triangular Pyramid: Triangular base with triangular faces.
• Pentagonal Pyramid: Pentagonal base with triangular faces.
4. Cylinders: Cylinders have two circular bases and a curved surface connecting them. They are often seen in objects like cans, tubes, and containers.
5. Cones: Cones have a circular base and taper to a single point at the top. Common examples include traffic cones and ice cream cones.
6. Spheres: Spheres are perfectly round, with all points equidistant from the center. Planets, balls, and marbles are typical spherical shapes.
7. Torus: A torus is a shape resembling a doughnut with a hole in the middle. It’s less common but can be found in objects like lifebuoys.
8. Ellipsoid: An ellipsoid is similar to a sphere but can be stretched or compressed along different axes, resulting in an elongated or flattened shape.
9. Irregular Shapes: Some 3D shapes do not fit into the standard categories mentioned above and have unique characteristics. These shapes vary widely and can include sculptures, architectural designs, and other creative constructs.

### List of Three Dimensional Shapes Chart ## 3D Shapes Formulas

Here are some common 3D shapes and their associated formulas

Shape Formula for Volume (V) Formula for Surface Area (SA)
Cube V = a³ (a is the length of one side) SA = 6a²
Rectangular Prism V = lwh (l is length, w is width, h is height) SA = 2lw + 2lh + 2wh
Sphere V = (4/3)πr³ (r is the radius) SA = 4πr²
Cylinder V = πr²h (r is the radius, h is the height) SA = 2πr² + 2πrh
Cone V = (1/3)πr²h (r is the radius, h is the height) SA = πr² + πr√(r²+h²)
Pyramid (General) V = (1/3)Bh (B is the area of the base, h is the height) SA = B + (1/2)Pl (P is the perimeter of the base, l is the slant height)
Sphere V = (4/3)πr³ (r is the radius) SA = 4πr²
Torus V = 2π²Rr² (R is the distance from the center of the tube to the center of the torus, r is the radius of the tube) SA = 4π²Rr
Ellipsoid V = (4/3)πabc (a, b, c are the semi-axes) SA ≈ 4π(√((a²b² + a²c² + b²c²)/3))

## Solved Examples of Three Dimensional Shapes

Example 1:  Find the volume of a rectangular prism with length 6 cm, width 4 cm, and height 5 cm.

Solution:

• The formula for the volume of a rectangular prism is V = lwh, where “l” is the length, “w” is the width, and “h” is the height.
• Substitute the given values: V = (6 cm)(4 cm)(5 cm) = 120 cubic centimeters.

Answer: The volume of the rectangular prism is 120 cubic centimeters.

###### Example 2:  Calculate the surface area of a cylinder with a radius of 3 cm and a height of 8 cm.

Solution:

• The formula for the surface area of a cylinder is SA = 2πr² + 2πrh, where “r” is the radius, and “h” is the height.
• Substitute the given values: SA = 2π(3 cm)² + 2π(3 cm)(8 cm) = 2π(9 cm²) + 2π(24 cm²) = 18π + 48π = 66π square centimeters.

Answer: The surface area of the cylinder is 66π square centimeters.

###### Example 3: Find the volume of a cone with a radius of 5 cm and a height of 12 cm.

Solution:

• The formula for the volume of a cone is V = (1/3)πr²h, where “r” is the radius and “h” is the height.
• Substitute the given values: V = (1/3)π(5 cm)²(12 cm) = (1/3)π(25 cm²)(12 cm) = 100π cubic centimeters.

Answer: The volume of the cone is 100π cubic centimeters.

###### Example 4:  Calculate the surface area of a sphere with a radius of 6 cm.

Solution:

• The formula for the surface area of a sphere is SA = 4πr², where “r” is the radius.
• Substitute the given radius: SA = 4π(6 cm)² = 4π(36 cm²) = 144π square centimeters.

Answer: The surface area of the sphere is 144π square centimeters.

Example 5: Find the volume of a triangular pyramid with a base area of 30 square centimeters and a height of 8 cm.

Solution:

• The formula for the volume of a triangular pyramid is V = (1/3)Bh, where “B” is the base area, and “h” is the height.
• Substitute the given values: V = (1/3)(30 cm²)(8 cm) = 80 cubic centimeters.

Answer: The volume of the triangular pyramid is 80 cubic centimeters.

###### Example 6: Calculate the surface area of a cuboid with dimensions: length = 7 cm, width = 5 cm, and height = 3 cm.

Solution:

• The formula for the surface area of a cuboid is SA = 2lw + 2lh + 2wh, where “l” is the length, “w” is the width, and “h” is the height.
• Substitute the given values: SA = 2(7 cm)(5 cm) + 2(7 cm)(3 cm) + 2(5 cm)(3 cm) = 70 square centimeters + 42 square centimeters + 30 square centimeters = 142 square centimeters.

Answer: The surface area of the cuboid is 142 square centimeters.

## FAQs

1. What are three-dimensional shapes?

Q: A: Three-dimensional shapes, also known as 3D figures, are objects that exist in three spatial dimensions, typically characterized by length, width, and height. Unlike two-dimensional shapes, 3D shapes have volume and can be viewed from various angles.

2. What is the difference between 2D and 3D shapes?

Q: A: The main difference is dimensionality. Two-dimensional (2D) shapes, like circles and squares, exist in a flat plane with only length and width. Three-dimensional (3D) shapes, such as cubes and spheres, have depth in addition to length and width.

###### 3. What are the properties of 3D shapes?

Q: A: Properties of 3D shapes include volume (the amount of space they occupy), surface area (the total area of their surfaces), and specific characteristics unique to each shape, such as edges, vertices, and faces.

4. How do you calculate the volume of a 3D shape?

Q: A: The formula for calculating the volume of different 3D shapes varies. For example, for a rectangular prism, it’s V = lwh (length × width × height). Spheres have the formula V = (4/3)πr³, where “r” is the radius.

5. Can you provide examples of common 3D shapes?

Q: A: Certainly! Common 3D shapes include cubes, spheres, cylinders, cones, pyramids, and prisms. Everyday objects like boxes, balls, and cans often represent these shapes.

###### 6. How do 3D shapes relate to real-world objects?

Q: A: Many real-world objects and structures are 3D shapes. For instance, buildings often have a cuboid shape, basketballs are spheres, and soda cans resemble cylinders. Understanding 3D shapes is crucial in architecture, engineering, and design.

7. What is the surface area of a 3D shape?

Q: A: The surface area is the total area of all the surfaces of a 3D shape. The formula varies for different shapes. For a cube, it’s SA = 6s² (where “s” is the side length), and for a cylinder, it’s SA = 2πr² + 2πrh (where “r” is the radius and “h” is the height).

8. How can I teach or learn about 3D shapes effectively?

Q: A: Effective teaching or learning about 3D shapes involves hands-on activities, visual aids, and practical applications. Utilize physical models, interactive software, and real-world examples to enhance understanding.