# Measurements of Sphere

• ### Introduction to Sphere

A sphere is a solid figure bounded by a curved surface, every point of which is equidistant from a fixed point called its center. The straight line starting at the surface, passing through the center and ending at the surface is called a diameter. The radius of a sphere is a straight line connecting its […]

• ### Surface Area of a Sphere

If we wind half of the surface of sphere with cord as shown in the figure, and then wind with exactly the same length of the cord the surface of a cylinder having just the same radius, the height of the cylinder equaling the diameter, we find that the cord covers half of the curved […]

• ### Volume of a Sphere

If a sphere is placed in a cylinder of the same diameter and with an altitude equal to the diameter, and the vacant spaces are filled with sand, the sand will be found to fill exactly one-third of the cylinder after the sphere is removed. Therefore, a sphere is equal to two-third of a cylinder […]

• ### Spherical Shell

Solid enclosed between two concentric spheres is called a spherical shell. For a spherical shell if and are outer and inner radii respectively, then the volume of the shell is             Or        Example: A sphere of radius 5cm is dropped into a cylindrical vessel partly filled with water. The diameter of the vessel is […]