**Right Circular Cylinder**:

A cylinder whose base is a circle is called circular cylinder. If the axis of the cylinder is perpendicular to its base then cylinder is called right circular cylinder.

If is the radius of the circular base, is height, is lateral surface area, is volume and is perimeter of the base, then

i.e (i) ( being radius)

or (ii) ( being diameter)

__Example__**:**

Find the cost of digging a well **3m** in diameter and **24m** in depth at the rate of **Rs.10** per cu.m.

__Solution__**:**

Given that

Diameter of the well

Radius of the well,

Depth of the well,

Volume of the earth excavated

Now, cost per cu. m

__Example__**:**

The volume of a cylindrical ring is **800 cu.cm**. The radius of cross section is **2cm**. Find the length of the ring.

__Solution__**:**

Given that

Radius of cross section,

Volume,

Let length of ring be

Now,