What will be the focal length of the camera when the scale of the aerial photograph is 1:4500, the flying height of the aircraft is 3780 meters above MSL and the average height of the terrain is 820 meters above sea level ?
657.8 mm
657.8 mm option is correct.
The scale of a vertical aerial photograph is the ratio of image distance to ground distance, and for a level terrain it equals the focal length of the camera divided by the flying height of the aircraft above the ground. Because the flying height is quoted above mean sea level while the terrain sits at its own elevation above MSL, the effective flying height above the ground surface must first be corrected.
Step 1 — effective height above terrain: \(H' = H - h = 3780 - 820 = 2960 \text{ m}\).
Step 2 — apply the scale equation \(\dfrac{1}{S} = \dfrac{f}{H'}\), i.e. \(f = \dfrac{H'}{S}\).
Step 3 — substitute: \(f = \dfrac{2960}{4500} = 0.65778 \text{ m} \approx 657.8 \text{ mm}\).
The alternative values 607.8, 555.9 and 595.7 mm all arise from using the wrong flying height (for example, ignoring the terrain correction and using 3780 m directly, or subtracting an incorrect terrain elevation), which changes the numerator of the scale equation but not the algebra itself.
Similar Questions
A geographic boundary marking the limits of the potential distribution of species is sometimes referred to as :
Granitoids with high magnesium composition that are commonly formed by plate collusion events in Archaean are called :
Banded iron formation closely related to glaciogenic marine sediments are called :
Which one of the following ore minerals show internal reflection ?
Which of the following is not a type of VHMS deposit ?
Self potential method is the most suitable method for prospecting of :
According to Zingg diagram _____ particles have a flattened cylindrical or disk-like shape such that one axis is much shorter than the other two with a ≈ b << c
A building is to be founded on a clay stratum. The water table is practically at ground surface level. Laboratory test show that the unit weight of the soil is r = 20 kN/m3 and classify the soil as a firm clay. The uniaxial compressive strength is qu = 150 kN/m2. Suppose that the footing will be square, 2 m wide, and the foundation depth will be 2 m below the ground surface, calculate the ultimate bearing capacity.
In a soil mechanics and engineering project, a stratigraphic column below the horizontal ground level of a wide valley is formed by 3 m of coarse gravels over a 12 m clay deposit. Below the clay is a highly permeable fractured sandstone. The water table in the gravel layer is 0.6 m below ground surface. In the sandstone substratum artesian condition with a piezometric height of 6 m above ground level exist. The gravel layer is very permeable and assumed to be hydrostatic. Determine the pore water pressure distribution.
A limestone classified as oomicrite by Folk’s classification but when combining Folk’s and Dunham’s classification it can be classified as :
Important Questions from Mixed Topic (MH-SET)
.................... is a client server application that identifies each host on the internet with a unique user-friendly name.
Every OS has a ................ or .......... which primarily resides in the main memory of the computer to perform some of the basic functions of the OS.
(i) Kernel
(ii) Interface
(iii) Nucleus
(iv) Compiler
Codes:
Which of the following are referred to as low level language?
(i) Machine language
(ii) Assembly language
(iii) High level language
(iv) Natural language
Codes:
Match the following:
List I List II (a) New York Public Library (i) Shelv AR (b) Miami University Augmented Research Group (ii) Smart library (c) Oula University Library (iii) Wolf Walk (d) North Carolina State University (iv) Find the future Codes:
Which part of the QR code represents the encoded data?
