In the area of measurement, we say that scale It is the constant ratio between any physical or chemical quantity that allows a comparison.
In the case of a drawing or map, we call the cartographic scale the mathematical relationship between the dimensions presented in the drawing and the real object it represents. These dimensions should always be taken in the same unit. The form of representation is as follows:
Scale = measured in drawing : measured on the actual object
Scale = measured in drawing / measured on the actual object
For example, if a map displays the scale 1:50means that 1 cm on the map is equivalent to 50 cm in the actual area.
If we want to indicate that each centimeter of a map represents 1 meter in the real area, we use the scale 1:100 or yet 1/100. Note that we have converted 1 meter to centimeters (100 centimeters), as both measurements must be in the same unit.
The indication of the scale usually appears on the drawing or map presented. For example:
The scale can also be represented in graphical form, which is made unit by unit, where each segment shows the relationship between the longitude of the representation and the actual area. For example, note the following graphical scale.
This representation is indicating that each segment of the graphical scale presented is equivalent to 400 kilometers of real area.
Regarding the size of the representation, we can use the following classification:
- Natural scale: Numerically represented as 1: 1 or 1/1. Occurs when the physical size of the object represented in the plane coincides with reality.
- Reduced scale: when the actual size is larger than the represented area. It is usually used in maps of territories or housing plans. Examples: 1: 2, 1: 5, 1:10, 1:20, 1:50, 1: 100, 1: 500, 1: 1000, 1: 5000, 1: 20000.
- Enlarged scale: When the graphic size is larger than the actual one. It is used to show minimal details of a particular area, especially small size spaces. Examples: 50: 1, 100: 1, 400: 1, 1000: 1.