A sphere is a threedimensional object that is round in shape. The sphere is defined in three axes, i.e., xaxis, yaxis and zaxis. This is the main difference between circle and sphere.
The points on the surface of the sphere are equidistant from the center. Hence, the distance between the center and the surface of the sphere are equal at any point. This distance is called the radius of the sphere. Examples of spheres are a ball, a globe, the planets, etc.
Table of contents: 
Sphere Definition
As discussed in the introduction, sphere is a geometrical round shape in threedimensional space. It is three dimensional solid, that has surface area and volume. Just like a circle, each point of the sphere is at a equal distance from the center.
Radius  The distance between surface and center of the sphere is called its radius 
Diameter  The distance from one point to another point on the surface of the sphere, passing through the center, is called its diameter. 
Surface area  The region occupied by the surface of the sphere is called its surface area 
Volume  The amount of space occupied by any spherical object is called its volume 
In the above figure, we can see, a sphere with radius ‘r’.
Unlike circle, which is a plane shape or flat shape, defined in XY plane, a sphere is defined in three dimensions, i.e. xaxis, yaxis and zaxis.
Important Facts:

Shape of Sphere
The shape of a sphere is round and it does not have any faces. Sphere is a geometrical three dimensional solid having curved surface. Like other solids, such as cube, cuboid, cone and cylinder, a sphere does not have any flat surface or a vertex or an edge.
The reallife examples of sphere is:
 Basket balls
 World Globe
 Marbles
 Planets
 Moon
Equation of a Sphere
In analytical geometry, if “r” is the radius, (x, y, z) is the locus of all points and (x0, y0, z0) is the center of a sphere, then the equation of a sphere is given by:
(x x_{0})^{2} + (y – y_{0})^{2} + (zz_{0})^{2} = r^{2}
Properties of a sphere
The important properties of the sphere are given below. These are also called attributes of sphere.
 A sphere is perfectly symmetrical
 It is not a polyhedron
 All the points on the surface are equidistant from the centre.
 It does not have a surface of centres
 It has constant mean curvature
 It has a constant width and circumference.
Sphere Formulas
The common formulas of the sphere are:
 Surface area
 Volume
Diameter of sphere  D = 2r, where r is the radius 
Surface area of sphere  SA = 4πr^{2} Square units 
Volume of sphere  V = 4/3 πr^{3} Cubic Units 
Surface Area of a Sphere
The surface area of a sphere is the total area covered by the surface of a sphere in a three dimensional space. The formula of surface are is given by:
The Surface Area of a Sphere(SA) = 4πr^{2} Square units 
Where “r” is the radius of the sphere.
Volume of a Sphere
The amount of space occupied by the object threedimensional object called a sphere is known as the volume of the sphere.
According to the Archimedes Principle, the volume of a sphere is given as,
The volume of Sphere(V) = 4/3 πr^{3} Cubic Units 
Related Articles on Sphere
 Area & Volume Of Sphere
 Difference between Circle and Sphere
 Equation of Sphere
 Surface Area of a Hemisphere
 Volume of Hemisphere
Solved Examples on Sphere
Example 1:
Find the volume of the sphere that has a diameter of 10 cm?
Solution:
Given, Diameter, d = 10 cm
We know that D = 2 r units
Therefore, the radius of a sphere, r = d / 2 = 10 / 2 = 5 cm
To find the volume:
The volume of sphere = 4/3 πr^{3} Cubic Units
V = (4/3)× (22/7) ×5^{3}
Therefore, the volume of sphere, V = 522 cubic units
Example 2:
Determine the surface area of a sphere having a radius of 7 cm
Solution:
Given radius = 7 cm
The Surface Area of a Sphere(SA) = 4πr^{2} Square units
SA = 4× (22/7)× 7^{2}
SA = 4 × 22 × 7
SA = 616 cm^{2}
Therefore, the surface area of a sphere = 616 square units.
Practice Questions
 Find the volume of the sphere if diameter = 10cm.
 If the radius of a sphere is 14 cm, then find its surface area.
 A cricket ball with radius ‘r’ cm and a basketball with radius ‘4r’ have volume in the ratio of?
 Metallic spheres of radii 3 cm, 4 cm and 5 cm, respectively, are melted to form a single solid sphere. Find the radius of the resulting sphere.
Register with BYJU’S – The Learning App to learn about other threedimensional shapes also watch interactive videos to learn with ease.
Frequently Asked Questions – FAQs
What is a sphere?
How many sides a sphere have?
Is sphere a circle?
What is Hemisphere?
What are the characteristics of a sphere?
What are the examples of sphere?
What is surface area and volume of sphere?
SA = 4πr^2 Square units
Volume of sphere is the space occupied by sphere in three dimension space. The formula is:
V = 4/3πr^3