FUNDAMENTAL SURVEYING Distance Measurement & Traversing 1 — Questions and Answers
Question 1: What is the primary purpose of a closed traverse in surveying?
- To measure elevations along a route
- To return to the starting point and check for closure error (Correct answer)
- To determine magnetic declination
- To calculate the area of a parcel using GPS only
Correct answer: To return to the starting point and check for closure error
A closed traverse returns to its starting point, allowing surveyors to detect and quantify errors by computing the closure.
Question 2: Which unit of length is equal to 66 feet and commonly used in US land surveying?
- Rod
- Chain (Correct answer)
- Vara
- Furlong
Correct answer: Chain
The Gunter's chain equals 66 feet and was the standard unit for US public land surveys, with 80 chains equaling one mile.
Question 3: What is 'slope distance' in surveying?
- The horizontal distance corrected for curvature
- The measured distance along an inclined surface (Correct answer)
- The vertical difference between two points
- The distance corrected for temperature
Correct answer: The measured distance along an inclined surface
Slope distance is the actual measured distance along an inclined line between two points, which must be reduced to horizontal distance for mapping.
Question 4: A traverse has a departure error of +0.32 ft and a latitude error of -0.45 ft. What is the linear closure?
- 0.77 ft
- 0.55 ft (Correct answer)
- 0.13 ft
- 0.21 ft
Correct answer: 0.55 ft
Linear closure = sqrt(0.32^2 + 0.45^2) = sqrt(0.1024 + 0.2025) = sqrt(0.3049) approximately 0.55 ft.
Question 5: What does 'precision' mean in the context of a traverse survey?
- The absolute accuracy of the measurements
- The ratio of linear closure to total traverse length (Correct answer)
- The number of decimal places recorded
- The agreement between GPS and total station readings
Correct answer: The ratio of linear closure to total traverse length
Traverse precision is expressed as the ratio of linear closure to the total perimeter length (e.g., 1:10,000).
Question 6: When using an electronic distance meter (EDM), what does the instrument measure directly?
- Horizontal distance only
- The time or phase shift of electromagnetic waves (Correct answer)
- The number of chain lengths
- The vertical angle to compute slope distance
Correct answer: The time or phase shift of electromagnetic waves
EDMs measure distance by transmitting electromagnetic waves and analyzing the phase shift or travel time of the return signal.
FUNDAMENTAL SURVEYING Distance Measurement & Traversing 1
What is the primary purpose of a closed traverse in surveying?