CST Level 1 Land Surveyor Certification Practice

What characteristic of a subtense bar is essential for its function?

1. It must be lightweight

2. It has sighting targets set apart by a specific distance

3. It is made of metal

4. It has adjustable length

The correct answer is: It has sighting targets set apart by a specific distance

For a subtense bar to effectively fulfill its purpose in surveying, it is crucial that it has sighting targets set apart by a specific distance. This characteristic allows surveyors to establish a reliable baseline for angle measurements. The spaced targets facilitate the accurate alignment of the instrument used during measurement, enabling the calculation of angles based on the distances between the targets. While being lightweight can be beneficial for ease of handling, it is not an essential characteristic for the functionality of a subtense bar. Similarly, the material of the bar, whether metal or otherwise, influences durability and weight but does not directly impact its foundational purpose in surveying. The adjustable length can enhance versatility for varying applications but is not a necessary attribute for the bar to perform its primary function. Thus, the placement of sighting targets at a specified distance is key to the proper operation of a subtense bar in land surveying practices.