CLASS-7
LATERAL SURFACE AREA OF CUBE

LATERAL SURFACE AREA (LSA) OF CUBE -

The lateral surface area of a cube is the area of the four vertical faces, excluding the top and bottom faces. Since a cube has all sides of equal length a, each face is a square with area .

Formula for Lateral Surface Area of a Cube

Lateral Surface Area = 4a²     

Where:-

  • a = length of a side of the cube

This formula is derived by adding up the areas of the four vertical square faces.


Example.1) If the length of the side of the cube is 5 cm, then find its lateral surface area.

Ans.)

If a cube has a side length of a = 5 cm,

Lateral Surface Area = 4 × (5)²

Lateral Surface Area = 4 × (5)² = 4 × 25 = 100cm²     (Ans.)


Example.2) If the length of the side of the cube is 6 cm, then find its lateral surface area.

Ans.)

Given,

Side length, a = 6 cm

LSA of cube = 4a²

LSA = 4 (6)²

LSA = 4 x 36 = 144 sq.cm       (Ans.)