Final answer:
Measurement devices used along the right of way likely include sensors for monitoring electrical and magnetic properties, but the exact types were not specified. Concerns about magnetic field measurements near DC power lines using coaxial cables are minimal, as the cables cancel out opposing currents. Standard tools for such measurements include tape measures, yard sticks, or meter sticks.
Step-by-step explanation:
The question appears to relate to the types of measurement devices used to monitor the conditions along the right of way on surface, in aerial settings, and at sub-stations. These devices are likely to be sensors or meters that measure electrical, magnetic, or other physical parameters at set intervals to ensure the safe and efficient operation of utility services. The mention of coaxial cables and their use in reducing electromagnetic fields in DC power lines suggests a focus on the engineering principles behind the design and maintenance of these utility systems.
As per the reference provided, the concern raised by a surveyor about magnetic field measurements near transmission lines is not an issue because coaxial cables are used, which effectively cancel opposing currents and thereby negate the generation of significant magnetic fields. This explanation indicates that the measurement devices being referred to are likely related to monitoring electromagnetic properties. It does not directly answer what specific measurement devices are located every 100 feet, but it suggests that concerns with magnetic fields are minimal due to the properties of the transmission lines.
To accurately measure distances such as the 100 meters mentioned or the width of a river in the example given, professionals use tape measures, yard sticks, or meter sticks. These tools can provide the precision required for surveying and construction tasks. Measurements in construction and engineering are commonly taken in meters as per the International System of Units (SI), which defines a meter based on the distance light travels in a vacuum in a specific fraction of a second.