LSIT Surveying Fundamentals 5

Question 1

The 'area by coordinates' method (Coordinate or Shoelace formula) computes area by using:

Accepted Answer

The cross product of X and Y coordinates of traverse vertices

Answer

The coordinate (Shoelace) formula computes area as half the absolute value of the sum of (X_i × Y_{i+1} − X_{i+1} × Y_i) for all consecutive vertices.

Question 2

What does the term 'geoid' represent in geodesy?

Accepted Answer

The equipotential surface of Earth's gravity field approximating mean sea level

Answer

The geoid is the irregular equipotential surface of Earth's gravity field that approximates mean sea level and defines orthometric (physical) heights.

Question 3

A surveyor sets up an instrument at point A and measures an angle to point B as 42°15'30". After rotating 180° and measuring the same angle in face-right, the reading is 222°15'00". What is the best value for the angle?

Accepted Answer

42°15'15"

Answer

The mean angle is found by averaging: face-left = 42°15'30" and face-right = 222°15'00" − 180° = 42°15'00"; average = 42°15'15".

Question 4

Which of the following best describes the 'three-wire leveling' technique?

Accepted Answer

Reading the top, middle, and bottom stadia wires on the rod to check accuracy and compute distances

Answer

Three-wire leveling reads all three horizontal crosshairs (top, middle, bottom stadia wires) on the leveling rod; the middle wire gives the elevation reading and the outer wires provide a check.

Question 5

In stadia surveying, if the stadia interval factor (K) is 100 and the rod intercept (s) is 1.25 ft, what is the horizontal distance (assuming a horizontal sight)?

Accepted Answer

125.00 ft

Answer

Stadia horizontal distance (level sight) = K × s = 100 × 1.25 = 125.00 ft (plus instrument constant C, usually negligible for modern instruments).

(LSIT) Land Surveyor in Training Practice Test

(LSIT) Land Surveyor in Training Practice Test

LSIT Surveying Fundamentals 5