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
Correct Answer :
B. At elongation
Related Questions
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 altitude of a circumpolar star is maximum when it is
At east elongation
At upper culmination
At west elongation
At lower culmination
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 azimuth when it is
At culmination
At elongation
Neither at culmination nor at elongation
Either at culmination or at elongation
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
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 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
In a truly vertical photograph,
Principal point coincides the isocenter
Iso-centre coincides the plumb point
Plumb point coincides the principal point
All the above
Pick up the incorrect statement from the following. The angular distance of heavenly bodies on observer's meridian measured from the pole, is
Co-declination
Co-altitude
Co-latitude
Polar distance
Right ascension of a heavenly body is its equatorial angular distance measured
Westward from the first point of Libra
Eastward from the first point of Aeries
Westward from the first point of Aeries
Eastward from the first point of Libra
If α is the observed altitude, the refraction correction in seconds, is
58 cot α
58 tan α
58 sin α
58 cos α
International Date Line is located along
Standard meridian
Greenwich meridian
Equator
180° longitude
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
Stellar astronomy deals with
Plane surveying
Geodetic surveying
Star observations
Planet observations
The Polaris remains below horizon at
10° N
50° N Latitude
Equator
5° S latitude
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
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
An aerial photograph may be assumed as
Parallel projection
Orthogonal projection
Central projection
None of these
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 average eye base is assumed as
58 mm
60 mm
62 mm
64 mm
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
The great circle along which the sun appears to trace on the celestial sphere with earth as centre during the year, is called
Equator
Celestial equator
Ecliptic
None of these
Longitudes are measured from 0° to
180° eastward
180° westward
180° east or westward
360° eastward
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 circle in which a plane tangent to the earth's surface at the point of observation, intersects the celestial sphere, is called
Visible horizon
Sensible horizon
Celestial horizon
True horizon
At lower culmination, the pole star moves
Eastward
Westward
Northward
Southward
While making astronomical observations, the observer is mainly concerned with
The direction of the vertical, the axis of rotation of the instrument
The direction of the poles of the celestial sphere
The direction of the star from the instrument
All the above
A nautical mile is
One minute arc of the great circle passing through two points
One minute arc of the longitude
1855.109 m
All the above
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