The latitude of a place was obtained by subtracting the zenith distance of a star from its declination, the observed star was between
Horizon and equator
Equator and zenith
Zenith and pole
Pole and horizon
Correct Answer :
C. Zenith and pole
Related Questions
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 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
For any star to be a circumpolar star, its
Declination must be 0°
Declination must be 90°
Distance from the pole must be less than the latitude of the observer
Hour angle must be 180°
In observations of equal precision, the most probable values of the observed quantities are those that render the sum of the squares of the residual errors a minimum, is the fundamental principle of
Gauss' Mid Latitude formula
D'Alembert's method
Legendre's method
Least square method
The negative sign is assigned to
Reduction to mean sea level
Correction for horizontal alignment
Correction for slope
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
Pick up the correct statement from the following:
Aerial photographs may be either vertical or oblique
Vertical photographs are taken with the axis of camera pointing vertically downward
Vertical photographs are used for most accurate maps
All the above
Limiting gradient for locating the base line on evenly-sloping ground, is
1 in 12
1 in 10
1 in 8
1 in 6
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
The latitude (λ) of a place and the altitude (α) of the pole are related by
λ = α
λ = 90° - α
λ = α - 90°
λ = 180° - α
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
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
If α is the observed altitude, the refraction correction in seconds, is
58 cot α
58 tan α
58 sin α
58 cos α
Invar tapes used for measuring base lines, is made of nickel-iron alloy containing nickel
24 %
36 %
40 %
60 %
The true and mean suns occupy the same meridian at the same time on
April 15
June 14
September 1
All the above
Pick up the correct statement from the following:
The horizontal direction of the pole is called astronomical north
The angle between the direction of true north and the direction of a survey line is called astronomical bearing
The astronomical bearing is generally called azimuth
All the above
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 slotted template method
Is prepared, by graphical method
Is suitable for large areas with less control
Is rapid and accurate
All the above
The plane at right angle to the zenith-nadir line and passing through the centre of the earth, is called
Rational horizon
True horizon
Celestial horizon
All the above
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 angle between the observer's meridian and declination circle of a heavenly body, is known as
Hour angle
Azimuth
Right ascension
Declination
A plate parallel is the line on the plane of the negative
Parallel to the principal line
Perpendicular to the principal line
Along the bisector of the angle between the principal line and a perpendicular line through principal plane
None of these
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
The net ground area of a vertical photograph 20 cm × 20 cm on scale 1 : 10,000 having overlaps 60% and 30%, is
0.50 sq km
0.56 sq km
0.60 sq km
0.64 sq km
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
At eastern elongation, the pole star moves
Eastward
Westward
Northward
Southward
If the general ground level of any area is 10% of the flying height, the principal points may be used as the centres of radial directions for small scale mapping even in tilted photograph up to
1°
2°
3°
4°
The stereo plotting instruments are generally manufactured on the principle of
Optical projection
Optical mechanism projection
Mechanical projection
All the above
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
If a star whose declination is 60° N culminates at zenith, its altitude at the lower culmination, is
10°
20°
30°
40°