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
Correct Answer :
D. 10 mm
Related Questions
The altitude of a circumpolar star is maximum when it is
At east elongation
At upper culmination
At west elongation
At lower culmination
If δ is the declination of the star and φ is the latitude of the observer, then the azimuth of the star at elongation is given by
sin z = sec φ . cos δ
cos z = sec φ . cos δ
tan z = sec φ . cos δ
None of these
The average eye base is assumed as
58 mm
60 mm
62 mm
64 mm
Triangulation surveys are carried out for locating
Control points for surveys of large areas
Control points for photogrammetric surveys
Engineering works, i.e. terminal points of long tunnels, bridge abutments, etc.
All the above
At western elongation, the pole star moves
Eastward
Westward
Northward
Southward
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 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
A star in northern sphere is said to transit
When its altitude is maximum
When its azimuth is 180°
When it is in south
All the above
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 distance between the projection centre and the photograph, is called
Principal distance
Principal line
Isocentric distance
Focal length
If two points differing by 1° of latitude and of the same longitude is 110 km apart on the earth, then two astronomical positions on the moon is about
10 km
25 km
30 km
50 km
The longitudes of two places at latitude 60° N are 93° E and 97° W. Their departure is
5100 nautical miles
5700 nautical miles
120 nautical miles
500 nautical miles
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
The sun's declination remains north between
March 21 to June 21
June 21 to September 21
September 21 to December 21
Both (a) and (b) of above
The main object of the astronomer to obtain
Astronomical latitude
Astronomical longitude
Astronomical bearing
All of these
Latitude of a place is the angular distance from
Greenwich to the place
Equator to the poles
Equator to the nearer pole
None of these
If the equatorial distance between two meridians is 100 km, their distance at 60° latitude will be
1000 km
800 km
600 km
500 km
Equation of time which is the difference between apparent solar time and mean solar time at any instant, vanishes during one year
Once
Twice
Thrice
Four times
The coverage is least if photography is
High oblique
Low oblique
Vertical
None of these
From the principal point the horizon point lies on the principal line at a distance of
f tan θ
f sin θ
f cot θ
f cos θ
The equation which is obtained by multiplying each equation by the coefficient of its un-knowns and by adding the equations thus formed, is known as
Observation equation
Conditional equation
Normal equation
None of these
The station which is selected close to the main triangulation station, to avoid intervening obstruction, is not known as
Satellite station
Eccentric station
False station
Pivot station
The moon rotates round the earth once in every
29 days
29.35 days
29.53 days
30 days
The scale of a tilted photograph of focal length f, taken from an altitude H, along the plate parallel through plumb point, is
f/H sec θ
f sec θ/H
f/H
f/H cos ½θ
The angle between the plane of the equator and the plane of the ecliptic, is known as obliquity of the ecliptic and its value is
22° 30'
23° 27'
23° 30'
24° 0'
Pick up the correct statement from the following:
The vertical plane containing the zenith, the station of observation and the celestial pole is the observer's meridian plane
The angle between the direction of star in vertical plane and the direction of the star in horizontal plane is called the altitude of the star
The complement of the altitude of star is called the zenith distance of the star
All the above
α and β are the angles subtended by a point of elevation h at their air station with respective plumb points. Photo scale and focal length of the lens being S and f respectively. Parallax displacement of the point due to relief, is
h tan α/S
h tan β/S
h (tan α + tan β)/S
h (tan α - tan β)/S
Pick up the correct statement from the following:
If the applied tension to the tape is more than the standard, the tension correction is positive
If the applied tension to the tape is less than the standard, the tension correction is negative
If the temperature during measurement is greater than the standard temperature, the temperature correction is positive
All the above
At eastern elongation, the pole star moves
Eastward
Westward
Northward
Southward
The most convenient co-ordinate system for specifying the relative positions of heavenly bodies on the celestial sphere, is
Altitude and azimuth system
Declination and hour angle system
Declination and right ascension system
Declination and altitude system