NCERT Class 9 Solutions: Surface Areas and Volumes (Chapter 13) Exercise 13.7 – Part 1

Download PDF of This Page (Size: 256K)

volume of cone=1/3 πr^2 h

Volume of Cone

volume of cone=1/3 πr^2 h

Relation between the height, radius and slant height of a cone.

Slant Height Radius and Height of Cone

Relation between the height, radius and slant height of a cone.

By the Pythagoras theorem,

Q-1 Find the volume of the right circular cone with

  1. Radius , height

  2. Radius , height

Solution:

  1. Radius

    Height

    Therefore, volume of the cone

  2. Radius Height

Volume of the cone

Q-2 Find the capacity in liters of a conical vessel with

  1. Radius , slant height

  2. Height , slant height

Solution:

  1. Radius Slant height

    Consider the height of the conical vessel . Then by applying Pythagoras theorem,

    Now, volume of the cone

    Therefore, capacity of the vessel

  2. Height Slant height

    Consider the radius of the conical vessel . Again using Pythagoras theorem,

Volume of the cone

Therefore, capacity of the vessel ,