Question

9. A survey crew wants to measure the height of a power line. The surveying crew set up a theodolite 138.32 feet from the power line. The surveying crew took the following vertical angle readings: • Angle to a point directly below the power line = 2° 16' 20". • Angle to the lowest point of the bottom conductor of the power line = 21°05' 15". What is the clearance under the power line? (10 points)

Answer 1

Actually there is no need of measuring the vertical angle to a point directly below power line in the calculation of clearance. If we were provided with RL's of station point and point below power line and asked to find RL of point below the power line, we need angle 2°16'20".