Fundamentals of Surveying (FS) Practice Exam

The effect of atmospheric pressure on EDM measurement is an example of a:

1. blunder

2. random error

3. one sigma error

4. systematic error

The correct answer is: systematic error

The effect of atmospheric pressure on Electronic Distance Measurement (EDM) is classified as a systematic error because it consistently influences measurements in a predictable manner. Systematic errors arise from factors that affect the measurement process in a uniform way, often due to the limitations or conditions of the measurement tools or methods used. In the case of EDM, atmospheric pressure affects the speed of light, which is essential for accurate distance measurements. These types of errors can be quantified and corrected because their relationship to the measurement process is well understood. As conditions like temperature and pressure change, they can lead to a consistent offset in the measurement results, differentiating them from blunders, which are typically random and arise from mistakes, or random errors, which do not consistently affect measurements in the same way. Understanding this concept underscores the importance of accounting for environmental factors in surveying practice to ensure precision and accuracy in measurements.