Question

If an index contour is labeled 500 and the next index contour is 600, with 4 intermediate lines in between, what is the contour interval?

• A. 25 meters
• B. 20 meters
• C. 10 meters
• D. 50 meters

Answer 1

Answer:

B. 20 meters

• The 100-meter difference divided by the 5 spaces created by the lines equals 20. • A Contour Interval represents the vertical distance of a single "jump" between any two adjacent lines. • When calculating this from a map, we look at the Rise (the difference between two labeled Index Contours) and divide it by the number of Intervals (the gaps or spaces) that exist between those two labels.