Levelling: Week 8

What is the key feature of the Height of Collimation (HOC) Method in levelling?

• It tracks the movement of the surveyor

• It calculates the height of the instrument at each point to determine elevation

• It uses a GPS to determine the elevation

• It measures the angle of the land surface

What is the purpose of adjusting the misclosure in levelling?

• To make sure all points are measured in the same unit

• To calculate the exact distance between points

• To correct for errors and ensure accurate height measurements

• To adjust for the time of day during the survey

If the initial RL is 34.449 meters and the final RL after completing a loop is 34.455 meters, what is the loop misclosure and the formula used?

• 0.006m / 6mm, Loop Misclosure = Final RL - Initial RL

• 0.007m / 7mm, Loop Misclosure = Final RL - Initial RL

• 0.006m / 6mm, Loop Misclosure = Initial RL - Final RL

• 0.007m / 7mm, Loop Misclosure = Initial RL - Final RL

What are the two main methods used for reducing levels in levelling?

• Rise and Fall Method and Height of Collimation Method

• Rise and Fall Method and Total Station Method

• Height of Collimation Method and Triangulation Method

• Rise and Fall Method and GPS Method

What are the formulas for acceptable misclosure based on accuracy classes?

• First-class: 2√n, Second-class: 6√n, Third-Class: 10√n

• First-class: 2√n, Second-class: 5√n, Third-Class: 10√n

• First-class: 4√n, Second-class: 5√n, Third-Class: 12√n

• First-class: 4√n, Second-class: 6√n, Third-Class: 12√n