free booknotes online

Help / FAQ

Win a $1000 or more Scholarship to college!

Please Take our User Survey

8.4 Circular Cylinders

Pillars, pipes etc. are examples of circular cylinders encountered daily.

A circular cylinder is two circles with the same radius at a finite distance from each other with their circumferences joined.

Figure 8.7

The definition of a circular cylinder is a prism with circular bases. The line joining the centers of the two circles is called the axis.

If the axis is perpendicular to the circles it is a right circular cylinder otherwise it is an oblique circular cylinder.

The lateral area of a right circular cylinder is the product of the circumference and the vertical distance between the two circles or the altitude ‘h’.

= Circumference ´ h

= 2pr ´ h

= 2 p r h square units.

where ’r’ is the radius of the circle.

The total area must include apart from the lateral area, the areas of the two circles.

        Area of the circle = pr2

\  Area of two circles = 2pr2

\         Total area       = 2prh + 2pr2

                                  = 2pr (h + r)

                                  = (h + r) square units

where C = circumference.

The volume of a right circular cylinder,

= area of the circle ´ height

= pr2 ´ h

= pr2h cubic units.


8.1 Introduction to solid geometry
8.2 Prism
8.3 The cuboid and the cube
8.4 Cylinders
8.5 Pyramids
8.6 Right circular cone
8.7 Sphere

Chapter 9

All Contents Copyright © All rights reserved.
Further Distribution Is Strictly Prohibited.

In Association with