## Surface area calculation

You can find the surface area of simple volumetric figures, such as prisms, by unfolding this figure on a plane. It is impossible to obtain a development of the ball in this way. The surface area of a sphere is found using the formula by multiplying the square of the radius by 4π. From this formula it follows that the area of a circle is four times less than the surface area of a ball with the same radius.

Surface areas of some astronomical objects: Sun – 6.088 x 10¹² square kilometers; Earth – 5.1 x 10⁸; thus, the surface area of the Earth is approximately 12 times smaller than the surface area of the Sun. The Moon’s surface area is approximately 3.793 x 10⁷ square kilometers, which is about 13 times smaller than the Earth’s surface area.

## Hectare

Real estate, especially land, is measured in hectares. One hectare is equal to 10,000 square meters. It has been in use since the French Revolution, and is used in the European Union and some other regions. Just like the macaw, in some countries the hectare is called differently.

## Geographical features with the largest area

** Country: Russia, 17,098,242 square kilometers, including land and water. The second and third largest countries by area are Canada and China. **

City: New York is the city with the largest area of 8683 square kilometers. The second largest city by area is Tokyo, occupying 6,993 square kilometers. The third is Chicago, with an area of 5,498 square kilometers.

City Square: The largest square, covering 1 square kilometer, is located in the capital of Indonesia, Jakarta. This is Medan Merdeka Square. The second largest area, at 0.57 square kilometers, is Praça doz Girascoes in the city of Palmas, Brazil. The third largest is Tiananmen Square in China, 0.44 square kilometers.

Lake: Geographers debate whether the Caspian Sea is a lake, but if so, it is the largest lake in the world with an area of 371,000 square kilometers. The second largest lake by area is Lake Superior in North America. It is one of the lakes of the Great Lakes system; its area is 82,414 square kilometers. The third largest lake by area is Lake Victoria in Africa. It covers an area of 69,485 square kilometers.

** References **

## Unit square

A unit square is a square with sides of one unit. The area of a unit square is also equal to one. In a rectangular coordinate system, this square is located at coordinates (0,0), (0,1), (1,0) and (1,1). In the complex plane, the coordinates are 0, 1, i and i 1, where i is an imaginary number.

## How to convert from m2 to m?

It is necessary to divide the area of the rectangle in m2 by the length of one of its sides. The result will be the length of the other side in m.

## Square centimeters to square meters | online calculator

Square centimeter (designation cm ^{ 2 }

) – a unit of area equal to the area of a square with side 1

centimeter.

2

square centimeter = 200

millimeters = 0.0002

square meters;

3

square centimeter = 300

millimeters = 0.0003

square meters;

4

square centimeter = 400

millimeters = 0.0004

square meters;

5

square centimeter = 500

millimeters = 0.0005

square meters;

6

square centimeter = 600

millimeters = 0.0006

square meters;

8

square centimeter = 800

millimeters = 0.0008

square meters;

## General information

Area is the size of a geometric figure in two-dimensional space. It is used in mathematics, medicine, engineering and other sciences, for example in calculating the cross-section of cells, atoms, or pipes such as blood vessels or water pipes.

## Convert dm2 to m2 | online calculator

Online calculator for converting Square decimeters ( dm ^{ 2 }

, sq. dm.

) to Square meters ( m ^{ 2 }

, sq.m.

) and vice versa, will help to express m ^{ 2 }

in dm ^{ 2 }

.

For example:

1

dm2 = 0.01

m2;

1

m2 = 100

dm2;

2

sq. dm. = 0.02

sq.m.;

## Planimeter

** The area can also be calculated using a special device – a planimeter. There are several types of this device, for example polar and linear. Also, planimeters can be analog and digital. In addition to other functions, digital planimeters can be scaled, making it easier to measure features on a map. **

## Area calculation

The area of the simplest geometric figures is found by comparing them with a square of known area. This is convenient because the area of the square is easy to calculate. Some formulas for calculating the area of geometric figures given below were obtained in this way.

## How many square meters are there in a meter?

1 m = 1 m2 / 1 m (one meter is equal to 1 square meter divided by 1 meter)

## Correlation of m² with other units of measurement

- 1 m ²

= 0.01 hundred

(1 weave is equal to 100 m ²

) - 1 m ²

= 10,000 cm²

(1 cm ²

equal to 0.0001 m ²

) - 1 m ²

= 100 dm²

(1 dm ²

equals 0.01 m ²

) - 1 m ²

= 0.000001 km²

(1 km ²

equal to 1,000,000 m ²

) - 1 m² = 0.0001 ha

(1 ha is equal to 10,000 m²)

** A common task, for example in school, is the need to express integer values (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.) area in mm2, cm2, dm2, m2, km2, ha… **

To convert units of measurement in the reverse direction, use the following online calculator.

## Unit conversion table

Length |

1 cm = 10 mm = 0.01 m |

1 dm = 10 cm = 0.1 m |

1 m = 100 cm = 10 dm |

1 km = 1000 m |

1 inch = 2.54 cm |

1 foot = 12 inches = 30.48 cm = 0.3048 m |

1 yard = 3 feet = 91.44 cm = 0.9144 m |

1 mile = 5280 feet = 1609.34 m = 1.609 km |

1 nautical mile =1.852 km |

1 m = 3.28 feet = 1.094 yards = 0.00062 miles |

1 cm = 0.393 inches |

Square |

1 cm ^{ 2 }= 100 mm ^{ 2 } |

1 dm ^{ 2 }= 100 cm ^{ 2 }= 0.01 m ^{ 2 } |

1 m ^{ 2 }= 100 dm ^{ 2 } |

1 km ^{ 2 }= 1,000,000 m ^{ 2 } |

1 ar (1 a) = 100 m ^{ 2 }= 1 weave |

1 hectare (1 ha) = 10,000 m ^{ 2 } |

1 sq. inch (square inch) = 6.4516 cm ^{ 2 } |

1 sq. square foot = 144 sq. inches = 929.03 cm ^{ 2 } |

1 sq. square yard = 9 sq. feet = 0.83613 m ^{ 2 } |

1 acre = 4046.86 m ^{ 2 } |

1 sq. square mile = 640 acres = 2.59 km ^{ 2 } |

1 m ^{ 2 }= 10.76 sq. ft = 1,196 sq. yards |

1 cm ^{ 2 }= 0.155 sq. inches |

Volume |

1 cm ^{ 3 }= 0.001 dm ^{ 3 }= 0.001 l |

1 liter = 1 dm ^{ 3 }= 61.03 cu. inch = 0.22 gallons |

1 cu. inch = 16.387 cm ^{ 3 }= 0.016 l |

1 cu. ft = 28316.8 cm ^{ 3 }=28.316 l |

1 cu. yard = 764555 cm ^{ 3 }= 764.555 l |

1 pint English = 0.568 l |

1 pint American = 0.473 l |

1 gallon English = 4.54 l |

1 US gallon = 3.78 l |

1 barrel of oil = 42 gallons = 158.988 l = 0.136 tons |

Weight |

1 kg = 1000 g |

1 c = 100 kg = 0.1 t |

1 t = 1000 kg = 10 c |

1 lb = 453.6 g = 0.4536 kg |

1 oz = 1/16 lb = 28.35 g |

1 g = 0.035 oz = 0.002205 lb |

1 kg = 2.2 lbs |

Troy system of measures for precious metals and precious stones |

1 grain = 64.8 mg |

1 carat = 3.086 grains = 0.2 g |

1 troy ounce = 31.10 g = 1/12 tr. lb = 480 grains |

1 troy pound = 373.24 g |

Temperature |

40°C = 104 F; 0°С= 32 F |

F = (°C *1.8) 32 |

°C = (F – 32)/1.8 |

A temperature difference of 1 °C is equivalent to a temperature difference of 1.8 F |

## Theorem on the properties of areas

According to the isoperimetric theorem, of all figures with the same perimeter, the circle has the largest area. If, on the contrary, we compare figures with the same area, then the circle has the smallest perimeter. The perimeter is the sum of the lengths of the sides of a geometric figure, or the line that marks the boundaries of this figure.

## Formulas for calculating area

- Square:

square side. - Rectangle:

product of the parties. - Triangle (side and height known):

the product of the side and the height (the distance from that side to the edge), divided in half. Formula: A = ½ah

, where A

– area, a

– side, and h

– height. - Triangle (two sides and the angle between them are known):

the product of the sides and the sine of the angle between them, divided in half. Formula: A = ½ab

sin(α), where A

– area, a

and b

are the sides, and α is the angle between them. - Equilateral triangle:

side squared divided by 4 and multiplied by the square root of three. - Parallelogram:

the product of a side and the height measured from that side to the opposite side. - Trapezoid:

the sum of two parallel sides multiplied by the height and divided by two. The height is measured between these two sides. - Circle:

the product of the square of the radius and π. - Ellipse:

product of semi-axes and π.

## Frequently asked questions:

- How many m ²

in one hundred

? Answer: one hundred. - How many m ²

in one square centimeter

? Answer: one ten thousandth. - How many m ²

in one square decimeter

? Answer: one hundredth part. - How many m ²

in one square kilometer

? Answer: million. - How many m ²

in one hectare

? Answer: ten thousand.