If the image of a triangulation station of R.L. 500 m is 4 cm from the principal point of a vertical photo taken from an altitude of 2000 m, above datum, the height displacement will be
A. 2 mm
B. 4 mm
C. 6 mm
D. 10 mm
Answer: Option D
This Question Belongs to Civil Engineering >> Surveying
For a vertical aerial photograph, the height displacement is:
d=rh/(H-h)
Where:
r=4cm= distance from principal point
h=500m= elevation of station
H=2000m= flying altitude above datum
d=4*500/(2000-500)
=2000/1500
=1.333cm
=13.33mm