Rotation of the camera at exposure about horizontal axis normal to the line of flight, is known as
Swing
Tilt
Tip
None of these
Correct Answer :
C. Tip
Related Questions
The maximum error in radial line assumption, is
h/H f tan θ
h/H f² tan θ
h/H f² sin θ
h/H f cos θ
On vertical photographs, height displacement is
Positive for points above datum
Negative for points below datum
Zero for points vertically below the air station
All the above
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
Polaris is usually observed for the determination of the azimuth when it is
At culmination
At elongation
Neither at culmination nor at elongation
Either at culmination or at elongation
The Polaris remains below horizon at
10° N
50° N Latitude
Equator
5° S latitude
With standard meridian as 82° 30' E the standard time at longitude 90° E is 8 h 30 m. The local mean time at the place will be
7 h 00 m
7 h 30 m
8 h 00 m
9 h 00 m
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 point on the photograph where bisector between the vertical line through optical centre of the camera lens and the plate perpendicular meets, is known as
Principal point
Isocenter
Plumb point
Perspective centre
Accidental errors
Do not follow any definite mathematical law
Cannot be removed by applying corrections to the observed values
Are generally small
All the above
The angular distance of a heavenly body from the equator, measured along its meridian, is called
Declination
Altitude
Zenith distance
Co-latitude
The station pointer is generally used in
Triangulation surveying
Astronomical surveying
Hydrographical surveying
Photogrammetric surveying
The parallax equation Δp = BmΔh/H - h is applicable to entire overlap of the photographs only if parallax is measured
Normal to base line
Parallel to base line
Both (a) and (b)
Neither (a) nor (b)
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 station where observations are not made, but the angles at the station are used in triangulation series, is known as
Satellite station
Subsidiary station
Pivot station
Main station
Pick up the correct statement for horizontal photographs.
Parallel lines do not appear parallel in central projection
The two sides of a road meet at the vanishing point
The lines parallel to the negative plane are projected as parallel lines
All the above
Polaris is usually observed for the determination of the latitude when it is
At culmination
At elongation
Neither at culmination nor at elongation
Either at culmination or at elongation
Pick up the in-correct statement from the following:
Correction for refraction is always negative
Correction for parallax is always positive
Correction for semi-diameter is always negative
Correction for dip is always negative
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 the first point of Aeries, the sun moves
Northward
Southward
From south to north of the equator
From north to south of the equator
In a tropical year, the numbers of sidereal days are
One less than mean solar days
One more than mean solar days
Equal to mean solar days
None of these
The value of geo-centric parallax to be added to the observed altitude of sun is
9 cos α
9 sin α
9 tan α
9 cot α
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
The position of the sun when its north declination is maximum is known as
Vernal equinox
Autumnal equinox
Summer solstice
Winter solstice
Homologous point is
Photo principal point
Ground principal point
Ground isocenter
All the above
The height displacement on a vertical photograph
Increases as the horizontal distance increases from the principal point
Increases as the ground elevation increases
Decreases as the flying height increases
All the above
The flying height of the camera is 1, 000 m above mean ground level, the distance of the top of a building from a nadir point is 10 cm and the relief displacement of building is 7.2 mm. The height of the building, is
52 m
62 m
72 m
82 m
The shortest distance between two places measured along the surface of the earth, is
Length of the equator between their longitudes
Length of the parallel between their longitudes
Length of the arc of the great circle passing through them
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
The zenith is the point on the celestial sphere
East of observer
West of observer
North of observer
South of observer
The parallax of a point on the photograph is due to
Ground elevation
Flying height
Length of air base
All the above