CBSE Notes Class 9 Maths Chapter 6 - Measuring Space: Perimeter and Area
These CBSE Class 9 Maths Notes Chapter 6 - "Measuring Space: Perimeter and Area" are based on the latest CBSE syllabus and the revised NCERT textbook, Ganita Manjari. They help students understand important concepts in a simple and structured manner, making it easier to revise key topics, formulas, and methods before examinations. These notes are also useful for homework, practice, and quick revision.
The Chapter " Perimeter and Area" in the revised 2026-27 syllabus introduces students to perimeter, area, surface area, and volume of different shapes and solids. It covers cubes, cuboids, cylinders, cones, spheres, hemispheres, pyramids, cross-sections, and capacity. The chapter also helps students understand and apply important formulas and concepts to solve problems effectively.
1.0Download CBSE Notes Class 9 Maths Chapter 6 - Measuring Space: Perimeter and Area
Download the CBSE Class 9 Maths Chapter 6 Notes PDF to revise important measurement concepts and understand how to calculate the space covered or enclosed by different shapes and solids. These notes are useful for quick revision, homework, practice, and exam preparation.
2.0Important Concepts CBSE Notes Class 9 Maths Chapter6 Perimeter and Area
Perimeter and Area
- Perimeter is the total length around a plane figure.
- Area is the region covered by a plane figure.
- For a square, the area depends on its side.
- For a rectangle, area depends on its length and breadth.
- For a circle, area depends on its radius.
- The circumference gives the distance around a circle.
Surface Area and Volume
A three-dimensional object has length, breadth, and height. Such objects are called solids.
- Surface area: Area covered by the surfaces of a solid.
- Volume: Space enclosed inside a solid.
- Examples include cubes, cuboids, cylinders, cones, spheres, pyramids, and prisms.
Cuboid
A cuboid has six rectangular faces, twelve edges, and eight vertices. Its opposite faces are equal.
Students learn about its total surface area, lateral surface area, volume, and diagonal. The area of the four walls of a room can also be found using the lateral surface area of a cuboid.
Cube
A cube is a cuboid in which length, breadth, and height are equal. A dice and an ice cube are common examples.
Important measurements include its total surface area, lateral surface area, volume, diagonal, and total length of all edges.
Cross-Section
A cross-section is the shape formed when a solid is cut through its length. For a solid with a uniform cross-section, volume depends on the area of the cross-section and its length.
Cylinder
A cylinder has two circular ends joined by a curved surface. Students learn to find its curved surface area, total surface area, and volume.
Cone
A right circular cone has a circular base and a vertex. Its main parts include the radius, vertical height, and slant height. The relation between these measurements can be understood using the Pythagoras theorem.
Sphere and Hemisphere
A sphere is a round solid such as a football or volleyball. A hemisphere is half of a sphere formed by cutting it through its centre.
The chapter covers the surface area and volume of spheres and hemispheres. It also explains spherical shells and hemispherical shells.
Pyramid
A pyramid has one polygonal base and triangular faces meeting at a common point called the apex. The chapter covers its base, height, slant height, lateral surface area, total surface area, and volume.
Effect of Changing Dimensions
Changing the length, breadth, height, radius, or slant height changes the surface area or volume of a solid. A small change in some dimensions, especially radius, can cause a large change in volume.
3.0Other Study Materials for Class 9 Maths
Students can use additional study materials along with these notes, such as:
4.0Why CBSE Notes Class 9 Maths - Measuring Space: Perimeter and Area
These notes cover the main points of the chapter in one place. Students can use them while studying, solving questions, and revising for tests.
- Easy revision: Find the main points quickly.
- Study help: Go through the topics one by one.
- Check answers: Look at the steps again while practising.
- Fewer mistakes: Check your calculations before moving to the next question.
- Before tests: Revise the chapter when you have less time.