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
Correct Answer :
C. Declination and right ascension system
Related Questions
The orthogonal projection of the perspective centre on a tilted photograph, is called
Nadir
Isocenter
Principal point
Plumb point
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
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 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
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
At upper culmination, the pole star moves
Eastward
Westward
Northward
Southward
The great circle whose plane is perpendicular to the axis of rotation of the earth, is called
Equator
Terrestrial equator
0° latitude
All the above
For adjusting a quadrilateral whose both the diagonals are observed, the equations of conditions involved, are
Two angle equations and two side equations
One angle equation and three side equations
Three angle equations and one side equation
None of these
The moon rotates round the earth once in every
29 days
29.35 days
29.53 days
30 days
H is the flying height above mean ground level and f is the principal distance of a vertical photograph. The mean scale of the photographs is
H. f
H/f
f/H
H + f
To have greatest coverage of the area, the type of photography used, is
High oblique
Low oblique
Vertical
None of these
The altitude of a heavenly body is its angular distance, measured on the vertical circle passing through the body, above
Equator
Horizon
Pole
None of these
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
The rate of change of parallax dp/dh with respect to change in h, may be expressed as
fB/(H - h)
fB/(H - h)2
fB/(H + h)
fB/(H + h)2
In triangulation surveys
The area is divided into triangular figures
Control stations are located from which detailed surveys are carried out
Sides are not measured excepting the base line
All the above
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
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 relief displacement of a building 72 m high on photograph is 7.2 mm and its top appears 10 cm away from principal point. The flying height of the camera, is
500 m
1000 m
1500 m
2000 m
The scale of a tilted photograph of focal length f taken from an altitude H, along the plate parallel through principal point is
f/H sec θ
f sec θ/H
f/H
f/H cos ½θ
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
Latitude of the observer's position is equal to altitude of
North pole
Pole star
Celestial pole
All 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
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 main object of the astronomer to obtain
Astronomical latitude
Astronomical longitude
Astronomical bearing
All of these
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
Pick up the correct statement from the following:
The principal point coincides with plumb point on a true vertical photograph
The top of a hill appears on a truly vertical photograph at greater distance than its bottom from the principal point
The top of a hill is represented on a vertical photograph at larger scale than the area of a nearby valley
All the above
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
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
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