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
Correct Answer :
A. δ - θ
Related Questions
The orthogonal projection of the perspective centre on a tilted photograph, is called
Nadir
Isocenter
Principal point
Plumb point
The length of a parallel of λ latitude between two meridians is equal to difference in longitudes multiplied by
sin λ
cos λ
tan λ
cot λ
According to Napier's Rules of circular parts for a right angled triangle, sine of middle part equals the product of
Tangents of two adjacent parts
Sines of two adjacent parts
Cosines of two adjacent parts
Both (a) and (b) above
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
The parallax of a point on the photograph is due to
Ground elevation
Flying height
Length of air base
All the above
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
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
If δ is the declination of the star and φ is the latitude of the observer then the hour angle of the star at elongation is given by
sin H = tan φ . cot δ
cos H = tan φ . cot δ
tan H = tan φ . cot δ
None of these
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
At eastern elongation, the pole star moves
Eastward
Westward
Northward
Southward
The nautical mile is the length of
1 minute of latitude
1 minute of longitude
1 degree of latitude
1 degree of longitude
In a tropical year, the numbers of sidereal days are
365
365.2224
365.2422
366.2422
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
At lower culmination, the pole star moves
Eastward
Westward
Northward
Southward
At western elongation, the pole star moves
Eastward
Westward
Northward
Southward
The distance between the projection centre and the photograph, is called
Principal distance
Principal line
Isocentric distance
Focal length
23 cm × 23 cm photographs are taken from a flying height with a camera of focal length of 3600 m and 15.23 cm respectively. A parallax difference of 0.01 mm represents
1 m
2 m
4 m
8 m
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
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
The altitudes of a circumpolar star at culminations are 70° and 10°, both culminations being north of zenith. The declination of the star, is
80°
70°
60°
50°
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
For plane ground the scale of a vertical photograph will be same as that of a tiled photograph along the photo parallel through
Isocenter
Plumb point
Principal point
None of these
The elevation of the star at elongation is obtained by
sin α = sin φ cosec δ
sin α = sin φ sec δ
sin α = cos φ sec δ
sin α = cos φ cosec δ
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 true and mean suns occupy the same meridian at the same time on
April 15
June 14
September 1
All the above
The latitude of the observer's position, is
Elevation of the elevated pole
Declination of the observer's zenith
Angular distance along the observer's meridian between equator and the observer
All the above
Pick up the in-correct statement from the following:
Apparent solar time is measured from the lower transit of the true sun
Mean solar time is measured from the lower transit of the mean sun
Sidereal time is measured from the lower transit of the first point of Aries
Sidereal time is measured from the upper transit of the first point of Aries
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
Pick up the incorrect statement from the following:
In truly vertical photographs without relief angles are true at the plumb point
In tilted photographs without relief, angles are true at the iso-centre
In tilled photographs with relief, angles are true at the principal point
None of these
The position of the sun when its north declination is maximum is known as
Vernal equinox
Autumnal equinox
Summer solstice
Winter solstice