Q : 3 A metal pipe is long. The inner diameter of a cross section is 4 cm, the outer diameter being (see Fig. ). Find its
(iii) total surface area.
Note: There are two surfaces, inner and outer.
Height of the cylinder,
Outer diameter =
Inner diameter =
Outer curved surface area =
Inner curved surface area =
Area of the circular rings on top and bottom =
The total surface area of the pipe =
Therefore, the total surface area of the cylindrical pipe is