The surface area, S, of a right cylinder is: In both these formulas, πr 2 is the area of the base and πrl or is the area of its lateral surface. If the height of the cone is given, the surface area is: Where r is the radius of the base and l is the slant height.
Where l is the length, w is the width, and h is the height of the rectangular prism. The surface area, S, of a rectangular prism is: The surface area, S, of a cube with edge, s, is: Many common objects have well-defined formulas for finding their surface areas. There are two rectangles with lengths of 7 and widths of 4, two rectangles with lengths of 9 and widths of 4, and two rectangles with lengths of 9 and widths of 7, so the surface area of the prism is: To find the surface area, S, of the rectangular prism, find the sum of the areas of each rectangle in the figure. The rectangular prism above is unfolded to create a 2D shape made up of the surfaces of the prism. This method works well for polyhedrons, but is not as effective for shapes with curved surfaces. The sum of the areas of all the surfaces in a shape is its surface area. The dimensions of each surface can then be measured in order to find their areas.
One common way to find the surface area of a 3D shape is to unfold the shape or figure into a flat ( 2D) figure, referred to as a net. Surface area is often measured in square units, such as square meters and square feet. The amount of cardboard used to make the box to the right is its surface area. In the figures above, the amount of material it takes to make the tent to the left is the tent's surface area. In geometry, the surface area of a 3D shape or geometric figure is the amount of space occupied by its surfaces. Home / geometry / volume and surface area / surface area Surface area