61. The cross hairs in the surveying telescope are placed
much closer to the eye-piece than to the objective lens
62. For which of the following permanent adjustments of theodolite, the spire test is used ?
adjustment of horizontal axis
63. The adjustment of horizontal cross hair is required particularly when the instrument is used for levelling
64. Which of the following errors is not eliminated by the method of repetition of
horizontal angle measurement ? error due to displacement of station
signals
65. The error due to eccentricity of inner and outer axes can be eliminated by
reading both verniers and taking the mean of the two
66. In the double application of principle of reversion, the apparent error is
four times the true error
67. Which of the following errors can be eliminated by taking mean of both face
observations ? error due to line of collimation not being perpendicular to horizontal axis
68. Which of the following errors be eliminated by taking both face observations ?
error due to horizontal axis not being perpendicular to the vertical axis ,index error i.e. error due to imperfect adjustment of the vertical circle vernier , error due to non-parallelism of the* axis of telescope level and line of collimation
69. If a tripod settles in the interval that elapses between taking a back sight
reading and the following foresight reading, then the elevation of turning point
will increase
70. If altitude bubble is provided both on index frame as well as on telescope of a
theodolite, then the instrument is levelled with reference to
altitude bubble on index frame,altitude bubble on telescope if it is to be used as a level
71. A 'level line' is a line parallel to the mean spheriodal surface of earth
72. The following sights are taken on a "turning point" foresight and backsight
73. The rise and fall method of levelling provides a complete check on
backsight,intermediate sight,foresight
74. If the R.L. of a B.M. is 100.00 m, the back- sight is 1.215 m and the foresight is
1.870 m, the R.L. of the forward station is 99.345 m
75. In an internal focussing type of telescope, the lens provided is concave
76. Which of the following errors can be neutralised by setting the level midway
between the two stations ? error due to both curvature and refraction
77. Height of instrument method of levelling is quicker and less tedious for large
number of intermediate sights
78. The rise and fall method provides a check on the reduction of intermediate point levels
79. If the staff is not held vertical at a levelling station, the reduced level calculated
from the observation would be less than true R.L
80.
Above table shows a part of a level field book. What is value of X? 1.1
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