How to Measure a Concave Surface Area

Find the concave surface area measurement.

Concave surface area, also known as curved surface area is often abbreviated as CSA. It is a mathematical measurement of curved objects such as a lenses, bottle bases or other similar shaped object. This type of mathematical formula is commonly introduced in elementary school when pre-algebra is being taught.

Things You'll Need

• Calculator (optional)

Instructions

1. Find the concave surface area by using the formula for finding the curved surface area of a hemisphere: 2πr². Multiply 2 by "pi" which is 3.14, and then by the radius squared. Squaring is done by multiplying the number by itself one time.

2. Try this example. With r = 8 feet, the surface area would be calculated as 2(3.14)(8 ft)².

3. You can find the radius by using the diameter given. The radius is the distance of any point from the circumference to the center point of a circle.

Tips & Warnings

• You need the diameter of the sphere to solve the problem.

• The parentheses in the formula example problem are equivalent to multiplication signs.

References

• EasyCalculation.com: Hemisphere Tutorial
• Mathguide.com: Surface Area of Common Solids