Question

All the formulas of lesson surface area volumes for class 9 please.

Answer 1

this your answer my dear friend

Answer 2

CUBOID

Let length = l, breadth = b and height = h units. Then

Volume = (l x b x h) cubic units.

Surface area = 2(lb + bh + lh) sq. units.

Diagonal = l2 + b2 + h2 units.

CUBE

Let each edge of a cube be of length a. Then,

Volume = a3 cubic units.

Surface area = 6a2 sq. units.

Diagonal = 3a units.

CYLINDER

Let radius of base = r and Height (or length) = h. Then,

Volume = (Πr2h) cubic units.

Curved surface area = (2Πrh) sq. units.

Total surface area = 2Πr(h + r) sq. units.

CONE

Let radius of base = r and Height = h. Then,

Slant height, l = h2 + r2 units.

Volume =Πr2h cubic units.

Curved surface area = (Πrl) sq. units.

Total surface area = (Πrl + Πr2) sq. units.

SPHERE

Let the radius of the sphere be r. Then,

Volume = 4\3Πr3 cubic units.

Surface area = (4Πr2) sq. units.

HEMISPHERE

Let the radius of a hemisphere be r. Then,

Volume = 2\3Πr3 cubic units.

Curved surface area = (2Πr2) sq. units.

Total surface area = (3Πr2) sq. units.

Note: 1 litre = 1000 cm3.