CST Mapping & Platting Techniques 2 — Questions and Answers
Question 1: On a map drawn at 1" = 100', a line measures 3.25 inches. What ground distance does it represent?
- 32.5 ft
- 325 ft (Correct answer)
- 3,250 ft
- 30.77 ft
Correct answer: 325 ft
3.25 in × 100 ft/in = 325 ft.
Question 2: What is the representative fraction for an engineering scale of 1" = 200'?
- 1:200
- 1:1,200
- 1:2,400 (Correct answer)
- 1:24,000
Correct answer: 1:2,400
200 ft × 12 in/ft = 2,400 inches, so the ratio is 1:2,400.
Question 3: On a topographic map, index contours are most commonly drawn heavier at which interval?
- Every second contour
- Every third contour
- Every tenth contour
- Every fifth contour (Correct answer)
Correct answer: Every fifth contour
Standard practice makes every fifth contour a heavier, labeled index contour.
Question 4: When contour lines cross a stream, the V-shape they form points in which direction?
- Downstream
- Upstream (Correct answer)
- Toward lower ground
- Toward the stream's mouth
Correct answer: Upstream
Contours bend upstream where they cross a drainage channel.
Question 5: Contour lines that are spaced very closely together indicate:
- A steep slope (Correct answer)
- A gentle slope
- Flat terrain
- A closed depression
Correct answer: A steep slope
Close spacing means elevation changes rapidly over a short horizontal distance.
Question 6: Which set of data is most commonly shown in a curve table on a subdivision plat?
- Radius, tangent offset, station, and elevation
- Degree of curve, superelevation, and design speed
- Radius, delta angle, arc length, chord bearing, and chord distance (Correct answer)
- Northing, easting, elevation, and point description
Correct answer: Radius, delta angle, arc length, chord bearing, and chord distance
Curve tables give the geometric elements needed to define and retrace each boundary curve.
Question 7: What is the main purpose of a vicinity map on a plat?
- To show the site's location relative to surrounding roads and landmarks (Correct answer)
- To show the elevation of every lot corner
- To list the owners of adjoining parcels
- To show the underground utility layout
Correct answer: To show the site's location relative to surrounding roads and landmarks
A vicinity map is a small-scale inset that helps users find the platted area.
CST Mapping & Platting Techniques 2
On a map drawn at 1" = 100', a line measures 3.25 inches.
What ground distance does it represent?