Working with Scale

Table of Contents

  1. Working with Scale
  2. Measuring Distance Using a Graphic Scale
  3. Calculating Slope When Determining Distance
  4. Converting Map Distance to Ground Distance Using a Representative Fraction (RF)
  5. Determining Scale Using a Representative Fraction

Measuring Distance Using a Graphic Scale

In this chapter, you learned that a scale bar is a graphic symbol representing ground distance. You also learned that scale bars come with an extension scale, which is an addition to the left of the zero on the scale bar. Scale bars have the advantage of maintaining the correct proportion when enlarging or reducing map size.

In this example, two points of interest, point A and point B are measured by drawing a line between them.

An image of the Arcata North USGS Topographic Quadrangle.
The stars labeled A and B are the points of interest. Changes in elevation are not yet factored into this measurement. Click to view the image in a larger size.

On a separate piece of paper, write down the answers to the following questions:

An image of the Arcata North USGS Topographic Quadrangle.
The purple line over the Kilometers/Meters scale bar is the approximate distance between point A and B. Changes in elevation are not yet factored into this measurement. Click to view the image in a larger size.
  1. What is the approximate distance in kilometers between point A and B?
  2. What is the approximate distance in meters between point A and B?
An image of the Arcata North USGS Topographic Quadrangle.
The purple line over the Miles scale bar is the approximate distance between point A and B. Changes in elevation are not yet factored into this measurement. Click to view the image in a larger size.
  1. What is the approximate distance in miles between point A and B?
An image of the Arcata North USGS Topographic Quadrangle.
The purple line over the Feet scale bar is the approximate distance between point A and B. Changes in elevation are yet factored into this measurement. Click to view the image in a larger size.
  1. What is the approximate distance in feet between point A and B?