Key Stage 4
Meaning
The surface area to volume ratio is the relationship between the volume of an object and the surface area of that object which can be used to explain how the properties of a material or object can change due to the size of the object.
About Surface Area to Volume Ratio
| As the size of an object decreases the surface area becomes larger compared to the volume of the object. | ||
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Area of 1 face x 6 : Volume 3x3 x 6 : 3x3x3 54cm2 : 27cm3 2cm2 : 1cm3 |
Area of 1 face x 6 : Volume 2x2 x 6 : 2x2x2 24cm2 : 8cm3 3cm2 : 1cm3 |
Area of 1 face x 6 : Volume 1x1 x 6 : 1x1x1 6cm2 : 1cm3 |
The surface area to volume ratio explains why
- A mouse will freeze quicker in cold temperatures than a bear because the larger the Surface Area the quicker an object can emit thermal energy and the smaller the volume the less thermal energy in the object.
A mouse has a large Surface Area compared to its volume so it loses thermal energy quickly.
- Multicellular organisms need specialised tissues with large surface areas to absorb nutrients and Oxygen because the larger the Surface Area the quicker an object can absorb chemicals and the larger the volume the more chemicals the object needs.
A multicellular organism has a large volume compared to its surface area so it needs parts of its body to have a large surface area to absorb enough nutrients and Oxygen.