Surface area : volume ratio

Definition

A comparison between an object's total surface area and its volume, written as $SA:V$ or calculated as $SA\div V$ .

Used by Edexcel and OCR

Specification 8.2 · Paper 2

A comparison of an object's surface area with its volume, showing how much surface is available for each unit of volume.
Doubling the side length has therefore halved the numerical surface area : volume ratio, even though the larger cube has more surface area overall.
Revise: Surface Area to Volume Ratio

Specification B2.2a · Paper 1 (Foundation), Paper 3 (Higher)

1
Calculate surface area and volume using the same length unit, then simplify the surface area : volume ratio to a number : 1.
2
When explaining why a large organism needs a transport system, link its smaller surface area : volume ratio to the needs of cells deep inside it.
3
Keep surface area in squared units and volume in cubed units before simplifying the surface area:volume ratio.

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A comparison of an object's surface area with its volume, usually simplified to the form $x:1$ .

Volume therefore grows more quickly than surface area, so surface area:volume ratio decreases.

Paper 1 (Foundation), Paper 2 (Foundation), Paper 3 (Higher), Paper 4 (Higher)

A comparison of an organism's surface area with its volume, written surface area:volume.
Comparing them gives the surface area:volume ratio.
Revise: Exchange Surfaces
Revise: Surface Area:Volume Ratio Calculations