Definition:Imperial/Area
Definition
The imperial units of area are based on a system of units in which each unit is the square of a corresponding imperial length unit.
The imperial units of area are as follows:
Square Inch
One square inch is equal to a square of side $1$ inch in length.
| \(\ds \) | \(\) | \(\ds 1\) | square inch | |||||||||||
| \(\ds \) | \(=\) | \(\ds 6 \cdotp 4516\) | \(\ds = 2 \cdotp 54^2\) | square centimetres |
The definition is exact.
Square Foot
One square foot is equal to a square of side $1$ foot in length.
| \(\ds \) | \(\) | \(\ds 1\) | square foot | |||||||||||
| \(\ds \) | \(=\) | \(\ds 144\) | \(\ds = 12^2\) | square inches | ||||||||||
| \(\ds \) | \(=\) | \(\ds 929\) | square centimetres |
Square Yard
One square yard is equal to a square of side $1$ yard in length.
| \(\ds \) | \(\) | \(\ds 1\) | square yard | |||||||||||
| \(\ds \) | \(=\) | \(\ds 9\) | \(\ds = 3^2\) | square feet | ||||||||||
| \(\ds \) | \(=\) | \(\ds 1296\) | \(\ds = 36^2\) | square inches |
Square Rod, Pole or Perch
One square rod, pole or perch is equal to a square of side $1$ rod, pole or perch in length.
| \(\ds \) | \(\) | \(\ds 1\) | square rod, pole or perch | |||||||||||
| \(\ds \) | \(=\) | \(\ds 30 \tfrac 1 4\) | \(\ds = \paren {5 \tfrac 1 2}^2\) | square yards | ||||||||||
| \(\ds \) | \(=\) | \(\ds 272 \tfrac 1 4\) | \(\ds = \paren {16 \tfrac 1 2}^2\) | square feet |
Square Chain
One square chain is equal to a square of side $1$ chain in length.
| \(\ds \) | \(\) | \(\ds 1\) | square chain | |||||||||||
| \(\ds \) | \(=\) | \(\ds 16\) | \(\ds = 4^2\) | square rods, poles or perches | ||||||||||
| \(\ds \) | \(=\) | \(\ds 484\) | \(\ds = 22^2\) | square yards |
Rood
One rood is equal to an oblong measuring $1$ chain by $2 \frac 1 2$ chains.
| \(\ds \) | \(\) | \(\ds 1\) | rood | |||||||||||
| \(\ds \) | \(=\) | \(\ds 2 \tfrac 1 2\) | square chains | |||||||||||
| \(\ds \) | \(=\) | \(\ds 40\) | \(\ds = 4 \times 10\) | square rods, poles or perches | ||||||||||
| \(\ds \) | \(=\) | \(\ds 1210\) | \(\ds = 22 \times 55\) | square yards | ||||||||||
| \(\ds \) | \(=\) | \(\ds 10 \, 890\) | \(\ds = 66 \times 165\) | square feet |
Acre
One acre is equal to an oblong measuring $1$ chain by $1$ furlong.
That is, measuring $4$ rods, poles or perches by $10$ chains.
| \(\ds \) | \(\) | \(\ds 1\) | acre | |||||||||||
| \(\ds \) | \(=\) | \(\ds 4\) | roods | |||||||||||
| \(\ds \) | \(=\) | \(\ds 10\) | square chains | |||||||||||
| \(\ds \) | \(=\) | \(\ds 160\) | \(\ds = 4 \times 40\) | square rods, poles or perches | ||||||||||
| \(\ds \) | \(=\) | \(\ds 4840\) | \(\ds = 22 \times 220\) | square yards | ||||||||||
| \(\ds \) | \(=\) | \(\ds 43 \, 560\) | square feet | |||||||||||
| \(\ds \) | \(\approx\) | \(\ds 0 \cdotp 4\) | hectares |
Square Mile
One square mile is equal to a square whose side measures $1$ mile.
| \(\ds \) | \(\) | \(\ds 1\) | square mile | |||||||||||
| \(\ds \) | \(=\) | \(\ds 640\) | \(\ds = 8 \times 80\) | acres |