Page 6 - Lesson Notes-Ch.13 SA and Volumes(Cuboids and Cubes)

length = breadth = height

Suppose the length of an edge =

Hence, surface area of the cube = 2( × + × + × )
2
2
2
2
2
= 2( + + ) = 2 × 3 = 6

Total Surface Area of Cube= 6
Lateral surface area of a Cube:
Lateral surface area of the cube = 2( × + × ) = 2 × 2 = 4
2
2

LSA of Cube =Area of 4 walls = 4

Length of the diagonal of cube ( ) = √ + +
= √ + +
2
2
2
= √3 = √3 unit.
2
Volume of the Cube and Cuboid

Volume of Cuboid:

The volume of the cuboid is equal to the product of the area of one
surface(base) and height.

Volume of the cuboid = × ℎ ℎ
= ( × ) × ℎ
Volume of the cuboid = ( × × ) cubic units

Volume of the Cube:

The volume of the cube is equal to the product of the area of the
base of the cube and height. As we know already, all the edges of
the cube are of same length.

Hence,

2
Volume of the cube = × ℎ
Since, = ℎ

Therefore,

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