Practice Test: Question Set - 20
1. A lens or combination of lenses in which the following defect is completely eliminated is called aplanatic
- (A) Spherical
aberration
- (B) Chromatic
aberration
- (C) Coma
- (D) Astigmatism
2. Pick up the method of surveying in which field observations and plotting proceed simultaneously from the following
- (A) Chain
surveying
- (B) Compass
surveying
- (C) Plan
table surveying
- (D) Tacheometric
surveying
3. For orientation of a plane table with three points A, B and C, Bessel's drill is
- (A) Align b through a and
draw a ray towards c, align a through b and
draw a ray towards c, finally align c through
the point of intersection of the previously drawn rays
- (B) Align c through a and
draw a ray towards b, align a through c and
draw a ray towards b, finally align b through
the point of intersection of the previously drawn rays
- (C) Align c through b and
draw a ray towards a, align b through c and
draw a ray towards a, finally align a,
through the point of intersection of the previously, drawn rays
- (D) In
the first two steps any two of the points may be used and a ray drawn towards
the third point, which is sighted through the point of intersection of
previously drawn rays in the final step.
4. Probable accidental error in precise levelling as recommended by International Geodetic Association should not exceed (where k is in kilometers.)
- (A) ± 0.1 √k mm
- (B) ± 0.5 √k mm
- (C) ± 1 √k mm
- (D) ± 5 √k mm
5. In a telescope the object glass of focal length 14 cm, is located at 20 cm from the diaphragm. The focussing lens is midway between them when a staff 16.50 m away is focussed. The focal length of the focussing lens, is
- (A) 5.24 cm
- (B) 6.24 cm
- (C) 7.24 cm
- (D) 8.24 cm
6. The main principle of surveying is to work
- (A) From
part to the whole
- (B) From whole
to the part
- (C) From higher
level to the lower level
- (D) From
lower level to higher level
7. If Δ is the angle of deflection of the curve, T1 and T2 are its points of tangencies, the angle between the tangent at T1 and long chord T1 T2 will be
- (A) Δ/4
- (B) Δ/3
- (C) Δ/2
- (D) Δ
8. The rise and fall method of reduction of levels, provides a check on
- (A) Back sights
- (B) Fore
sights
- (C) Intermediate
sights
- (D) All
of these
9. The surface of zero elevation around the earth, which is slightly irregular and curved, is known as
- (A) Mean
sea level
- (B) Geoid
surface
- (C) Level
surface
- (D) Horizontal
surface
10. If the rate of gain of radial acceleration is 0.3 m per sec3 and full centrifugal ratio is developed. On the curve the ratio of the length of the transition curve of same radius on road and railway, is
- (A) 2.828
- (B) 3.828
- (C) 1.828
- (D) 0.828
11. The apparent error on reversal is
- (A) Equal to the
actual error
- (B) Twice
the actual error
- (C) Thrice
the actual error
- (D) None
of these
12. If the long chord and tangent length of a circular curve of radius R are equal the angle of deflection, is
- (A) 30°
- (B) 60°
- (C) 90°
- (D) 120°
13. In precision theodolite traverse if included angles are read twice and the mean reading accepted using both verniers having a least count of 30". Assuming the instrument to be in perfect adjustment, linear measurements correct to 6 mm per 30 metre tape duly corrected for temperature, slope and sag, the angular error of closure not to exceed (where n is the number of traverse legs)
- (A) 50" √n
- (B) 30" √n
- (C) 60" √n
- (D) None of these
14. The diaphragm of a stadia theodolite is fitted with two additional
- (A) Horizontal
hairs
- (B) Vertical
hairs
- (C) Horizontal
and two vertical hairs
- (D) None of
these
15. Magnetic bearing of a survey line at any place
- (A) Remains
constant
- (B) Changes
systematically
- (C) Varies
differently in different months of the year
- (D) Is
always greater than true bearing