PS Surveying Methods & Techniques 2 ā Questions and Answers
Question 1: In a closed traverse, the algebraic sum of latitudes and departures should equal:
- The total perimeter distance
- Zero (Correct answer)
- The area of the traverse
- The azimuth closure
Correct answer: Zero
In a geometrically closed traverse, the sum of all northing components (latitudes) and all easting components (departures) must each equal zero for perfect closure.
Question 2: The Bowditch (Compass) Rule distributes traverse closure error proportionally to:
- The angle at each station
- The length of each course (Correct answer)
- The bearing of each course
- The elevation change of each course
Correct answer: The length of each course
The Bowditch Rule distributes linear closure error to each course in proportion to the length of that course relative to the total traverse perimeter.
Question 3: Which method is most appropriate for locating a point that is inaccessible due to an obstacle?
- Direct chaining
- Radiation
- Intersection from two known stations (Correct answer)
- Open traverse
Correct answer: Intersection from two known stations
Intersection (triangulation from two or more known control points) allows a surveyor to locate an inaccessible point by measuring angles from accessible stations.
Question 4: A backsight reading of 4.52 ft and a foresight reading of 7.18 ft are taken with a level. The elevation of the foresight turning point is:
- Benchmark elevation + 2.66 ft
- Benchmark elevation ā 2.66 ft (Correct answer)
- Benchmark elevation + 11.70 ft
- Benchmark elevation ā 11.70 ft
Correct answer: Benchmark elevation ā 2.66 ft
The elevation difference is FS ā BS = 7.18 ā 4.52 = +2.66, so the foresight point is 2.66 ft lower than the benchmark (subtract from HI).
Question 5: In stadia surveying, the horizontal distance formula using a horizontal line of sight is:
- D = K Ć s + C (Correct answer)
- D = K / s + C
- D = s / K + C
- D = K Ć sĀ² + C
Correct answer: D = K Ć s + C
The stadia formula for horizontal distance is D = K Ć s + C, where K is the stadia interval factor (typically 100), s is the rod intercept, and C is the stadia constant.
Question 6: A total station using the EDM measures slope distance. To obtain horizontal distance, the surveyor must also measure the:
- Magnetic declination
- Vertical angle (Correct answer)
- Index error
- Zenith azimuth
Correct answer: Vertical angle
Horizontal distance = Slope distance Ć cos(vertical angle); the vertical angle is required to reduce slope distance to horizontal distance.
Question 7: The method of 'resection' in surveying allows a surveyor to:
- Set a line perpendicular to a baseline
- Determine their own position by observing known control points (Correct answer)
- Extend a straight line past an obstacle
- Measure an inaccessible distance by triangulation
Correct answer: Determine their own position by observing known control points
Resection determines an unknown instrument station location by measuring angles to three or more known control points (e.g., Pothenot's method).
PS Surveying Methods & Techniques 2
In a closed traverse, the algebraic sum of latitudes and departures should equal: