Self Study Distance Solutions

Problem (1)

Calibration data

Tape is 99.995 ft long, fully supported, at 68°F, and under 18 pounds of pull.

Its cross-sectional area is 0.003 sq inches with a 3.0x10⁷ psi modulus of elasticity, 6.5x10^-6 ft/ft/°F thermal coefficient, and 0.0195 lb/ft weight.

Use data

A distance was measured in two 50 ft end support segments, two 100 ft end support segments, three fully supported 100 ft segments, and one 78.46 ft end support segment, all using a 25 pound pull. The temperature was 80°.

To the nearest 0.001 ft, what is the corrected distance?

Solution

Sketch

Incorrect tape length

 Temperature

Pull

Sag

Corrected Distance

 Corr'd dist = 678.462 ft