# Surface area to volume ratio

relation between the surface area and the volume of an object

The surface area to volume ratio of an object is the relationship between two measurements. It is the ratio of Surface area to volume. It shows the comparison between the size of the outside of an object and the amount inside. Small or thin objects have a large surface area compared to the volume. This gives them a large ratio of surface to volume. Larger objects have small surface area compared to the volume so they have a small surface area to volume ratio. A large lump, for example, has a small ratio, and may be smashed into powder to give it a large surface to volume ratio.

Two common ways of writing it are sa/vol or SA:V. Either of these say to divide the surface area by the volume. This shows how much surface area is required for each unit of volume.

## Example

 Cube 1 measures 1 meter on each side. It has a surface area of 6 m2. Surface area = length x length (or length2) multiplied by the number of sides (6). It has a volume of 1 cubic meter. Volume = length x length x length or length3. Its ratio is 6 m2 per cubic meter. Cube 2 had sides that measured 10m Its surface area is 102 x 6 = 600 m2 Its volume is 1000 cubic meters Its ratio is 0.6 m2 per cubic meter.