The scale of a vertical photograph of focal length f taken from height of H metres above M.S.L., at a point of reduced level h, is
f/H
f/(H + h)
f/(H - h)
(H - h)/f
Correct Answer :
C. f/(H - h)
Related Questions
If θ and δ be the latitude of a place and declination of a star respectively, the upper culmination of the star will be north of zenith if its zenith distance, is
δ - θ
θ - δ
θ + δ
(θ + δ)/2
Parallax bar measures
Parallax
Height
Parallax difference
Height difference
The solar tidal force divided by lunar tidal force is
1/3
1/2
3/4
5/4
The point at which sun's declination changes from north to south, is known as
First point of Aeries
First point of Libra
Vernal Equinox
Both (b) and (d) of the above
The scale of the photography taken from a height of 300 m, with a camera of focal length 15 cm, is
1 : 10,000
1 : 15,000
1 : 20,000
1 : 30,000
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
2 mm
4 mm
6 mm
10 mm
To obtain photographs of an area of 1000 m average elevation, on scale 1 : 30, 000, with a camera of 30 cm focal length, the flying height is
4000 m
5000 m
6000 m
7000 m
A star is said to elongate
When the star momentarily moves vertically
When the angle at the star of the spherical triangle is 90°
When the star's declination is greater than the observer's latitude
All the above
The latitude of a place was obtained by subtracting the declination of a star from its zenith distance, the observed star was between
Horizon and equator
Zenith and pole
Equator and zenith
Pole and horizon
In a spherical triangle ABC, right angled at C, sin b equals
sin a cos A
cos a sin A
tan a cot A
cot A tan a
The angular distance of a heavenly body from the equator, measured along its meridian, is called
Declination
Altitude
Zenith distance
Co-latitude
If E is the spherical excess and R the radius of the earth, the surface area of the triangle, is
πR²E/90°
πR²E/180°
πR²E/270°
πR²E/360°
The parallax of a point on the photograph is due to
Ground elevation
Flying height
Length of air base
All the above
In a spherical triangle ABC right angled at C, sin b equals to
sin c sin B
cos c cos B
tan c tan B
sin c cos B
Pick up the correct statement from the following:
The horizontal direction of the pole is called astronomical north
The angle between the direction of true north and the direction of a survey line is called astronomical bearing
The astronomical bearing is generally called azimuth
All the above
If the altitudes of a star at its upper and lower transits are 60° 30' and 19° 30' respectively, the latitude of the place, is
30°
35°
40°
45°
The stereo plotting instruments are generally manufactured on the principle of
Optical projection
Optical mechanism projection
Mechanical projection
All the above
The necessary geometrical condition for triangulation adjustment is:
The sum of the angles around a station should be 360°
The sum of the three angles of a plane triangle should be 180°
The sum of the eight angles of a braced quadrilateral should be 360°
All the above
The nearest star is so far away from the earth that the directions to it from two diametrically opposite points on the earth differs less than
0.01 second
0.001 second
0.0001 second
None of these
At lower culmination, the pole star moves
Eastward
Westward
Northward
Southward
At upper culmination, the pole star moves
Eastward
Westward
Northward
Southward
Pick up the correct statement from the following:
Aerial photographs may be either vertical or oblique
Vertical photographs are taken with the axis of camera pointing vertically downward
Vertical photographs are used for most accurate maps
All the above
Pick up the correct statement from the following:
The measured stereoscopic base of photographs is obtained by dividing the air base in metres by the mean scale of the photograph
The difference between the absolute parallax of two points depends upon the difference in their elevations
The line joining the principal point of a photograph and the transferred principal point of the adjoining photograph, is called stereoscopic base
All the above
The product of the distances of plumb point and horizon point of a vertical photograph from its principal point, is
f2
2f2
3f2
½f
In triangulation surveys
The area is divided into triangular figures
Control stations are located from which detailed surveys are carried out
Sides are not measured excepting the base line
All the above
The scale of a tilted photograph of focal length f taken from an altitude H, along the plate parallel through principal point is
f/H sec θ
f sec θ/H
f/H
f/H cos ½θ
The Polaris describes a small circle round the pole whose radius is approximately
1°
2°
3°
4°
Pick up the correct statement from the following:
Refraction correction is zero when the celestial body is in the zenith
Refraction correction is 33' when the celestial body is on the horizon
Refraction correction of celestial bodies depends upon their altitudes
All the above
The net ground area of a vertical photograph 20 cm × 20 cm on scale 1 : 10,000 having overlaps 60% and 30%, is
0.50 sq km
0.56 sq km
0.60 sq km
0.64 sq km
The principal plane contains
Nadir point
Iso centre
Principal point
All the above