A perfectly symmetrical 3 – Dimensional circular shaped object is a Sphere. The line that connects from the center to the boundary is called radius of the square. You will find a point equidistant from any point on the surface of a sphere. The longest straight line that passes through the center of the sphere is called the diameter of the sphere. It is twice the length of the radius of the sphere.
Formulas of a Sphere
There are four main formulas for a sphere which include sphere diameter formula, sphere surface area, and sphere volume. All these formulas are mentioned in the table given below and an example is also provided here.
|Diameter of a Sphere||D = 2 r|
|Surface Area of a Sphere||A = 4 π r2|
|Volume of a Sphere||V = (4 ⁄ 3) π r3|
Solved Examples Using Formulas of a Sphere
Question: Calculate the diameter, surface area and volume of a sphere of radius 9 cm?
r = 9 cm
Diameter of a sphere
= 2 × 9
Surface area of a sphere
4πr2 = 4 × π × 92
= 4 × π × 81 = 1017.87 cm
Volume of a sphere = 4/3 πr3
= 4/3 π. 93
= 3053.628 cm3