A right triangle ABC with sides 5 cm, 12 cm and 13 cm is revolved about the side 12 cm. Find the volume of the solid so obtained.
Solution:
Since the triangle is revolved about the side 12 cm, a solid cone is formed with a height of 12 cm and radius of the base of 5 cm as shown below.
Volume of a cone having radius 'r', and height 'h', = 1/3πr²h
Radius of the cone, 'r' = 5 cm
Height of the cone, 'h' = 12 cm
Volume of the cone = 1/3πr²h
= 1/3 × π × 5 cm × 5 cm × 12 cm
= 100π cm³
Volume of the cone is 100π cm³.
☛ Check: NCERT Solutions for Class 9 Maths Chapter 13
Video Solution:
A right triangle ABC with sides 5 cm, 12 cm and 13 cm is revolved about the side 12 cm. Find the volume of the solid so obtained.
NCERT Solutions for Class 9 Maths Chapter 13 Exercise 13.7 Question 7
Summary:
It is given that the right triangle ABC with sides 5 cm, 12 cm and 13 cm is revolved about the side 12 cm. We have found that the volume of the cone 100π cm³.
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