MCQ Surveying Flashcards

In GPS surveying, dilution of precision (DOP) refers to:

Answer: The geometric effect of satellite configuration on position accuracy

DOP quantifies how satellite geometry amplifies ranging errors; a lower DOP value indicates a stronger geometric configuration and better accuracy.

A stadia rod is held vertically on a point. The upper wire reads 4.85 ft and the lower wire reads 3.25 ft with the stadia interval factor K=100. What is the horizontal distance (instrument level, zero vertical angle)?

Answer: 160 ft

Stadia interval = 4.85 – 3.25 = 1.60 ft; horizontal distance = K × interval = 100 × 1.60 = 160 ft.

When using the compass rule to adjust a traverse, corrections are distributed proportionally based on:

Answer: The length of each course relative to the total perimeter

The compass (Bowditch) rule distributes the closure error to each course in proportion to its length as a fraction of the total traverse perimeter.

In photogrammetry, the flying height above ground is 6,000 ft and the camera focal length is 6 inches. What is the photo scale denominator?

Answer: 1:12,000

Scale = f / H = (6/12) ft / 6,000 ft = 0.5/6,000 = 1/12,000.

The legal description 'NW¼ of the SW¼ of Section 12' encompasses how many acres?

Answer: 40 acres

A full section = 640 acres; the SW¼ = 160 acres; the NW¼ of that = 40 acres.

Which of the following best describes the principal of 'working from the whole to the part' in surveying?

Answer: Establishing control points first, then locating details from them

This fundamental principle requires establishing a framework of control points first, minimizing error propagation when locating subordinate detail.

A horizontal curve has a radius of 800 ft and a central angle (Δ) of 32°. What is the tangent length (T)?

Answer: 228.7 ft

T = R × tan(Δ/2) = 800 × tan(16°) = 800 × 0.28675 ≈ 229.4 ft ≈ 228.7 ft.