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
Correct Answer :
D. All the above
Related Questions
If 16 flight lines are run perpendicular to an area 30 km wide, their spacings on a photographical map on scale 1 : 50,000 , will be
1 cm
2 cm
3 cm
4 cm
If S is the sum of three angles of a spherical triangle, the spherical excess equals
S - 90°
S - 180°
S - 270°
S - 360°
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
The relation between the air base (B), photographic base (b), flying height (H) and the focal length (f) of a vertical photograph, is
B = bH/f
B =f/bH
B = b/fH
B = H/bf
The average eye base is assumed as
58 mm
60 mm
62 mm
64 mm
If the distance between the projectors is altered by a movement along X-axis of one projector,
The length of the air base is increased
The scale of the model is altered
y-parallax is not affected
All the above
Sidereal day
Is the period of time taken by the earth in making a complete rotation with reference to stars
Is slightly shorter than an ordinary solar day
Is divided into the conventional hours, minutes and seconds
All the above
Systematic errors
Always follow some definite mathematical law
Can be removed by applying corrections to the observed values
Are also known as cumulative errors
All the above
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
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
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
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
Pick up the correct statement from the following:
North end of the polar axis is known as North Pole
South end of the polar axis is known as South Pole
Point where polar axis when produced northward intersects the celestial sphere, is known as north celestial pole
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
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 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°
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
For mapping any country
Geodetic triangulation of greatest possible sides and accuracy is carried out
Primary triangles are broken down into secondary triangles of somewhat lesser accuracy
Secondary triangles are further broken into third and fourth order triangles, the points of which are used for detail surveys
All the above
Pick up the incorrect statement from the following. In a spherical triangle
Every angle is less than two right angles
Sum of the three angles is equal to two right angles
Sum of the three angles less than six right angles and greater than two right angles
Sum of any two sides is greater than the third
The point on the celestial sphere vertically below the observer's position, is called
Zenith
Celestial point
Nadir
Pole
Stellar astronomy deals with
Plane surveying
Geodetic surveying
Star observations
Planet observations
To have greatest coverage of the area, the type of photography used, is
High oblique
Low oblique
Vertical
None of these
Latitude of the observer's position is equal to altitude of
North pole
Pole star
Celestial pole
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
When a star is between the pole and the horizon, the relationship between latitude (λ), zenith distance (z) and declination δ, is
θ = z + δ
θ = δ - z
θ = 180° - (z + δ)
θ = (z + δ) - 180°
If a star whose declination is 60° N culminates at zenith, its altitude at the lower culmination, is
10°
20°
30°
40°
Pick up the correct statement from the following:
Ursa Minor's remains always north of pole star
Polar star remains always north of Polaris
Polaris remains always north of Ursa Minor's
Ursa Minor's pole star and Polaris are the names of the same star
The angular distance of a heavenly body from the equator, measured along its meridian, is called
Declination
Altitude
Zenith distance
Co-latitude
The sidereal day is the time interval between two successive upper transits of
Mean sun
First point of Aries
First point of Libra
The polar star
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