Angles, Bearings & Azimuths Flashcards
6 cards from real FUNDAMENTAL SURVEYING practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Angles, Bearings & Azimuths flashcards as text
What instrument is used to directly measure horizontal and vertical angles in modern surveying?
Answer: Total station or theodolite
A total station (or theodolite) measures both horizontal and vertical angles electronically, and most also measure distances with a built-in EDM.
Measuring a horizontal angle in both the direct and reverse positions of a theodolite (face left and face right) is done to:
Answer: Eliminate instrumental errors such as eccentricity and collimation error
Face-left and face-right measurements cancel out systematic instrumental errors including horizontal collimation error, vertical axis error, and circle eccentricity.
A vertical angle of -5 degrees 30 minutes indicates the line of sight is:
Answer: Directed downward (a depression angle)
Negative vertical angles (depression angles) indicate the target is below the instrument's horizontal plane.
What is 'grid north' in the context of US state plane coordinates?
Answer: The north direction of the state plane coordinate grid lines
Grid north is the direction of the northing (y-axis) grid lines in a state plane coordinate system, which differs slightly from true north except along the central meridian.
Converting a bearing of S 45 W to an azimuth gives:
Answer: 225 degrees
S 45 W means 45 degrees west of south; azimuth = 180 + 45 = 225 degrees.
What is the 'angle to the right' (clockwise angle) measurement method?
Answer: Measuring all horizontal angles clockwise from the backsight to the foresight
Angles to the right are measured clockwise from the backsight direction to the foresight direction, the standard convention used in most US traverse surveys.