

For example, if you have a hexagonal prism, the bases are the two hexagons on either end of the prism. The bases of a prism are the two unique sides that the prism is named for. The first word we need to define is base.
SURFACE AREA OF A PRISM FORMULA AND IMAGE HOW TO
The base is in the shape of a square, so A(base) = l².Hi, and welcome to this video on finding the Volume and Surface Area of a Prism!īefore we jump into how to find the volume and surface area of a prism, let’s go over a few key terms that we will see in our formulas.

R² + h²= s² so taking the square root we got s = √(r² + h²) But that's not a problem at all! We can easily transform the formula using Pythagorean theorem: Usually, we don't have the s value given but h, which is the cone's height.(sector area) = (π × s²) × (2 × π × r) / (2 × π × s)įor finding the missing term of this ratio, you can try out our ratio calculator, too! (sector area) / (large circle area) = (arc length) / (large circle circumference) so: The formula can be obtained from proportions, as the ratio of the areas of the shapes is the same as the ratio of the arc length to the circumference: The area of a sector - which is our lateral surface of a cone - is given by the formula:Ī(lateral) = (s × (arc length)) / 2 = (s × 2 × π × r) / 2 = π × r × s The arc length of the sector is equal to 2 × π × r. It's a circular sector, which is the part of a circle with radius s ( s is the cone's slant height).įor the circle with radius s, the circumference is equal to 2 × π × s. Let's have a look at this step-by-step derivation: The base is again the area of a circle A(base) = π × r², but the lateral surface area origins maybe not so obvious: A = A(lateral) + A(base), as we have only one base, in contrast to a cylinder.We may split the surface area of a cone into two parts: Surface area of a pyramid: A = l × √(l² + 4 × h²) + l², where l is a side length of the square base and h is a height of a pyramid.īut where do those formulas come from? How to find the surface area of the basic 3D shapes? Keep reading, and you'll find out! Surface area of a triangular prism: A = 0.5 × √((a + b + c) × (-a + b + c) × (a - b + c) × (a + b - c)) + h × (a + b + c), where a, b and c are the lengths of three sides of the triangular prism base and h is a height (length) of the prism. Surface area of a rectangular prism (box): A = 2(ab + bc + ac), where a, b and c are the lengths of three sides of the cuboid.

Surface area of a cone: A = πr² + πr√(r² + h²), where r is the radius and h is the height of the cone. Surface area of a cylinder: A = 2πr² + 2πrh, where r is the radius and h is the height of the cylinder. Surface area of a cube: A = 6a², where a is the side length. Surface area of a sphere: A = 4πr², where r stands for the radius of the sphere. The formula depends on the type of solid.

Our surface area calculator can find the surface area of seven different solids.
