Surface Area of Solids

Cube:
A cube is a three-dimensional figure, a solid made up of six equal squares called faces.



The lateral surface area (LSA) of a cube = 4l².

Total surface area (TSA) = 6l².

Cuboid:
A cuboid is a solid made up of six rectangles, called faces. The total area of a cuboid is the sum of the areas of these faces.



The lateral surface area (LSA) of a cuboid = 2h (l + b).

Total surface area (TSA) = 2(lb + bh + hl).

Cylinder:
A cylinder is a solid composed of two congruent circles in parallel planes.



Curved surface area (CSA) of a cylinderical pillar = 2πrh.

Total surface area (TSA) = 2πr(r + h).

Area of the four walls of a room = 2 x (l + b) x h = Perimeter of the floor x height.

where l = length, b = breadth and h = height.

Hollow cylinder
A solid bounded by two coaxial cylinders of the same height and different radii is called a hollow cylinder.

Surface area of each base = π(R² - r²).

Curved surface area (CSA) = 2πh(R + r).

Total surface area (TSA) = 2π(R + r)(h + R - r), where R = external radius, r = internal radius and h = height.