GATE-2018 (24) :Wyllie – Time average equation

CSIR-NET 2013

82. Assume that the relief displacement for a tower A is 3mm and the radial distance form the center of the photo to the top of the tower is 50mm .If the flying height is 1350m above the base of the tower, find the height of the tower.

A) 62m                B) 56m                 C) 76m                  D)81m

Solution:

Formula:

h=(H*Δr) /r_T -----------------(1)

The above equation tells us that the flying height above the base of the object (H) times the relief displacement in the photograph (Δr) divided by the radial distance from the principal point to the top of the object (r_T) is equal to the height of the object (h).

Given values from above problem

Flying height (H) = 1350 m =1350000mm

Relief displacement (Δr)= 3 mm

Radial distance from the principal point to the top of the object (r_T) =50 mm

Above values substitute in eq (1)

h=( 1350000*3) /50

h=(27000*3)

h=81000 mm

therefore, height of the tower (h) = 81m

Please follow this link: http://www.seos-project.eu/modules/3d-models/3d-models-c02-p02-s01.html