RPLS Quality Control Procedures 2

Question 1

When performing a closure check on a traverse, what does a closure ratio of 1:5,000 indicate?

Accepted Answer

For every 5,000 units measured, there is 1 unit of linear error

Answer

A closure ratio of 1:5,000 means there is one unit of linear misclosure for every 5,000 units of total traverse length.

Question 2

Which QC procedure best detects systematic errors in GPS baseline measurements?

Accepted Answer

Comparing independently computed baselines that form closed loops

Answer

Closing GPS baselines into loops and computing the loop misclosure is the primary method for detecting systematic errors in GNSS surveys.

Question 3

A surveyor re-measures a distance three times and gets 100.02, 100.03, and 100.01 feet. What is the most probable value?

Accepted Answer

100.02 ft

Answer

The arithmetic mean (100.02 + 100.03 + 100.01) / 3 = 100.02 ft is the most probable value for a series of direct measurements.

Question 4

What is the purpose of using a 'check shot' to a known point during a total station survey?

Accepted Answer

To verify the instrument setup has not shifted or been disturbed

Answer

Periodically observing a check shot to a known point confirms that the instrument setup remains undisturbed and the orientation is still valid.

Question 5

In leveling, which check confirms that the sum of backsights minus the sum of foresights equals the change in elevation?

Accepted Answer

Page check

Answer

A page check verifies arithmetic by confirming that ΣBS − ΣFS = last elevation − first elevation on each page of field notes.

(RPLS) Registered Professional Land Surveyor Practice Test