On this page, you will find Surface Areas and Volumes Class 9 Notes Maths Chapter 13 Pdf free download. CBSE NCERT Class 9 Maths Notes Chapter 13 Surface Areas and Volumes will seemingly help them to revise the important concepts in less time.

## CBSE Class 9 Maths Chapter 13 Notes Surface Areas and Volumes

### Surface Areas and Volumes Class 9 Notes Understanding the Lesson

Cuboid: With length T, breadth ‘b’ and height ‘h’

(a) Volume = lbh

(b) Total surface area = 2(lb + bh + hl)

(c) Lateral surface area = 2h(l + b) (c)

(d) Diagonal = \(\sqrt{l^{2}+b^{2}+h^{2}}\)

(e) Perimeter = 4(l + b + h)

Cube: With side ‘a’

(a) Volume = a^{3}

(b) Total surface area = 6a^{2}

(c) Lateral surface area = 4a^{2}

(d) Diagonal = \(\sqrt{3} a\)

(e) Perimeter = 12a

Right circular cylinder: With radius ‘r’ and height ‘h’

(a) Volume = πr^{2}h

(b) Curved surface area = 2πrh

(c) Total surface area = 2πr(h + r)

Right circular cone: With radius ‘r’, height ‘h’ and slant height ‘l’

(a) Volume = \(\frac{1}{3}\) πr^{2 }h or \(\frac{1}{3}\) x (Area of the base) x height

(b) Curved surface area = πrl, where \(l=\sqrt{h^{2}+r^{2}}\)

(c) Total surface area = πr(l + r)

Sphere: With radius ‘r’

(a) Volume =\(\frac{4}{3}\) πr^{3
}^{
}(b) Surface area = 4πr^{2}

Hemisphere: With radius ‘r’

(a) Volume = \(\frac{2}{3}\)πr^{3}

(b) Curved surface area = 2πr^{2}

^{
}(c) Total surface area = 3πr^{2}