In this lesson, we will learn
A cube is a three-dimensional figure with six equal square faces. The surface area of a cube is the sum of the area of the six squares that cover it.
The figure above shows a cube. The dotted lines indicate edges hidden from your view.
If s is the length of one of its sides, then the area of one face of the cube is s2.
Since a cube has six faces the surface area of a cube is six times the area of one face.
Surface area of a cube = 6s2
Find the surface area of a cube with a side of length 3 cm
Given that s = 3
Surface area of a cube = 6s2 = 6(3)2 = 54 cm2
The following videos show how to find the surface area of a cube.
This video shows how to find the length of a cube given the surface area.
Another way to look at the surface area of a cube is to consider a net of the cube. The net is a 2-dimensional figure that can be folded to form a 3-dimensional object.
Imagine making cuts along some edges of a cube and opening it up to form a plane figure. The plane figure is called the net of the cube.
The following net can be folded along the dotted lines to form a cube.
We can then calculate the area of each square in the net and then multiply the area by 6 to get the surface area of the cube.
There are altogether 11 possible nets for a cube as shown in the following figures. Notice that the surface area of each of the net is the same.
This video shows how to use nets and 3-dimensional figures to find surface area of cubes and prisms.
We welcome your feedback, comments and questions about this site or page. Please submit your feedback or enquiries via our Feedback page.