Surface Area Calculator — cube, cylinder, sphere

Kira jumlah luas permukaan kubus, kuboid, silinder, kon atau sfera — dengan tepat dalam sebutan π, dengan setiap bahagian ditunjukkan.

Formula

A_{\text{cuboid}} = 2(lw + lh + wh)

Six rectangular faces, in three matching pairs.

A_{\text{cylinder}} = 2\pi r^2 + 2\pi r h

Two circular ends plus the curved side.

A_{\text{cone}} = \pi r^2 + \pi r l,\quad l = \sqrt{r^2 + h^2}

The base plus the curved surface, using the slant height l.

A_{\text{sphere}} = 4\pi r^2

Four times the area of a circle with the same radius.

The two circular ends: 2π × 3² = 18π.

The curved side: 2π × 3 × 5 = 30π.

Total surface area = 18π + 30π = 48π ≈ 150.796447.

Surface area is the area of the outside (how much paint covers it); volume is the space inside (how much it holds).

The distance from the tip down the side to the edge of the base: l = √(r² + h²).