FINALReview - Final Study Questions GEM3331 Spring 2006...

Final Study Questions – GEM3331 Spring, 2006
These are sample questions only -- actual questions will vary.
Measurement Theory & Lab 1 "20 Measurements"
1. Defend choosing 3-sigma as a level of blunder.
2. Name five ways of testing and inspecting repeated measurements to see if they follow a classical normal
distribution.
3. Explain how you would measure the width of a 30 meter room by visual estimation (1 sigma = +- 0.5m
) within 10 millimeters of true at the 2-sigma confidence level.
4. What is the standard deviation of the mean? Explain the difference between this and just standard
deviation.
5.Explain the three types of survey errors, how they behave, how you detect them, and how to eliminate
them if possible.
Random Theodolite Errors & Lab 2
1. Explain why the standard deviation of 20 total station angle readings would be larger when you recenter
the total station between each reading.
2. Explain the reason that short backsights should be avoided in construction layout. Give a numerical
example to show the reason. .
3. An angle of about 180 degrees is measured with a 1-sigma theodolite centering error and target
centering error of 2mm (measured lateral to the line of sight). Discuss the required length of sight
distances to keep the expected angle uncertainty below 5" at the 3-sigma confidence level. (presume errors
of reading and pointing are zero)
4. Explain the law of accumulation and give an example of how it works.
5. Explain the "radius of wobble" and how to calculate it for tribrach or prism centering.
6. For measuring a point's location by angle and distance from one station, calculate the required distance
in order to have "balanced precision" if angles are measured +- 10 seconds. Explain the concept of
balanced precision.