A line scale, also known as a graphic scale or bar scale, is used to calculate real-world distances on a map by visually representing the map's scale. Here's how it works:
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Measure the Distance on the Map: Use a ruler to measure the distance between two points of interest on the map. This measurement will be in centimeters (cm) or inches, depending on your ruler.
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Compare to the Line Scale: Place the ruler alongside the line scale. Align the zero mark of the ruler with the beginning of the line scale.
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Read the Corresponding Distance: Observe where the other end of your measured distance aligns with the line scale. The number indicated on the line scale at that point represents the corresponding real-world distance (usually in kilometers or miles).
Example:
Imagine you measure a distance of 5 cm between two cities on a map. You then place your ruler on the line scale, and find that 5 cm on your ruler aligns with the "10 km" mark on the line scale. This means that the real-world distance between those two cities is 10 kilometers.
In Summary: A line scale provides a visual reference to convert map distances (measured with a ruler) into real-world distances.
