Measurement and Data Collection 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 Measurement and Data Collection flashcards as text
A steel tape calibrated at 68°F is used at 95°F. If the tape is 100 ft long, what is the temperature correction?
Answer: +0.018 ft
Temperature correction = 0.0000065 × (95−68) × 100 = 0.0000065 × 27 × 100 ≈ +0.018 ft.
Which of the following best describes a GPS carrier-phase measurement?
Answer: Counting the number of complete wavelengths between satellite and receiver
Carrier-phase measurement counts the number of full and fractional wavelengths of the carrier signal between satellite and receiver.
What is the purpose of a plumb bob or optical plummet in surveying?
Answer: To center the instrument over a ground point
A plumb bob or optical plummet is used to align the instrument's vertical axis directly over the survey point on the ground.
What is the term for the error caused by the line of sight not being perpendicular to the horizontal axis of a theodolite?
Answer: Collimation error
Collimation error occurs when the line of sight (collimation axis) is not perpendicular to the horizontal (trunnion) axis.
In total station surveying, what does 'PPM' correction refer to?
Answer: Parts per million atmospheric correction applied to EDM measurements
PPM (parts per million) corrections are applied to EDM distance measurements to account for atmospheric temperature and pressure effects.
What is the typical accuracy of a survey-grade GNSS receiver in static mode after post-processing?
Answer: ±1–5 cm
Survey-grade GNSS in static mode with post-processing typically achieves ±1–5 cm horizontal accuracy.