03
Nov
Class 9 - Surface areas and Volumes, Math - Class 9 | NCERTClass 9 math tutorials, curved surface area, cylinder, lateral surface area, math, mathemafia, mathematics, NCERT, surface area
Question 3: A metal pipe is 77 cm long. The inner diameter of a cross section is 4 cm, the outer diameter being 4.4 cm (see Fig. 13.11). Find its
- inner curved surface area,
- outer curved surface area,
- total surface area.
Prerequisite
A closed cylinder has 3 surfaces:
- Curved or lateral surface
- Top
- Base
The formula to calculate the curved surface area and total surface area are quite simple to learn and derive.
Lateral or curved surface area of cylinder = 2πrh
r = radius, h = height (or length)
Total surface area of cylinder = 2πr ( r + h )
r = radius, h = height (or length)
It is recommended to understand the core concept of area, surface area and volume before we attempt any question based on these concepts.
Derivation of formula – Surface area of cylinder
Chapter 13 – Surface areas and Volumes
Concepts
- Area / Surface area / Volume – Introduction
- Surface Area of Cube and Cuboid
- Volume Of Cuboid and Cube
- Surface Area of Right Circular Cylinder
- Volume and capacity of Cylinder
- Right circular Cone
- Surface Area of Right circular Cone
- Volume of Cylinder vs Cone
- Litres and Cubic centimetre (cm³)
- Cubic meters to litres