How to Find the Radius of a Sphere When Given the Volume

••• Westend61/Westend61/GettyImages

The radius of a sphere hides inside its absolute roundness. A sphere's radius is the length from the sphere's center to any point on its surface. The radius is an identifying trait, and from it other measurements of the sphere can be calculated, including its circumference, surface area and volume. The formula to determine the volume of a sphere is 4/3π multiplied by r, the radius, cubed, where π, or pi, is a nonterminating and nonrepeating mathematical constant commonly rounded off to 3.1416. Since we know the volume, we can plug in the other numbers to solve for the radius, r.

    Multiply the volume by 3. For example, suppose the volume of the sphere is 100 cubic units. Multiplying that amount by 3 equals 300.

    Divide this figure by 4π. In this example, dividing 300 by 4π gives a quotient of 23.873.

    Calculate the cube root of that number. For this example, the cube root of 23.873 equals 2.879. The radius is 2.879 units.

Related Articles

How to Calculate the Moment of Inertia
How to Calculate the Diameter of a Circle From a Linear...
How to Figure the Cubic Yards in a Circle
How to Convert the Area of a Circle to Square Feet
How to Calculate the Volume and Circumference of a...
How to Calculate the Volume of an Octagon
How to Calculate Volume From Centimeters
How to Calculate the Height of a Cone From the Volume
How to Calculate Volume of a Rectangular Prism
How to Find the Radius of a Cone
How to Calculate Cubic Inches in a Cylinder
How to Calculate Sphere Size
How to Find and Calculate the Weight of a Sphere
How to Calculate Volume of a Circular Cylinder
How to Find the Cross Sectional Area of a Pipe
Volume Vs. Mass Density
How to Find the Radius of a Cylinder When Given the...
How to Convert Meter to Liter
How to Convert Diameter to Square Centimeters
How to Calculate a Circular Area