81. The difference between a is smaller than R.L. of first poinlevel line and a horizontal line is that
level line is a curved line while horizontal line is a straight line
82. The sensitivity of a bubble tube can be increased by increasing the diameter of the tube
83. With the rise of temperature, the sensitivity of a bubble tube decreases
84. Refraction correction partially eliminates curvature correction
85. The R.L, of the point A which is on the floor is 100 m and backsight reading on A is 2.455 m. If the foresight reading on the point B which is on the ceiling is 2.745 m, the R.L. of point B will be 105.20
86. As applied to staff readings, the corrections for curvature and refraction are
respectively - and +
87. Which of the following arithmetic checks can be applied in rise and fall method ? ΣB.S. - ΣF.S. = ΣRise - ΣFall= Last R.L. - First R.L
88. What is the arithmetic error in the following table ?
The height of instrument (H.I.) should be 103.00
89. The following consecutive readings were taken with a dumpy level:
0.695. 1.525, 2.395, 0.635, 0.605, 0.805,0.125
The instrument was shifted after the third and fifth readings. The readings 2.395 and 0.635 respectively represent F.S. and B.S
90. In Question no. 89, the number of stations 5
91. In Question no. 89, the R.L. of last point is smaller than R.L. of first point
92.
The above table shows a part of a level field book. The value of X should be
100.00
93.The correction for refraction as applied to staff reading is
94. The following consecutive readings were taken with a dumpy level and a 3 m staff on a continuously sloping ground. 0.425, 1.035, 1.950, 2.360, 2.950, 0.750,
1.565, 2.450, 0.320, 1.025, 2.165, 2.955 Which of the following readings are back
sights ? 0.425, 0.750, 0.320
95. A level was set up at a point A and distance to the staff station B was 100 m.
The net combined correction due to curvature and refraction as applied to the
staff reading is - 0.000673 m
96.In levelling between two points A and B on opposite banks of a river, the following readings were taken
If R.L of A is 100.00 m, the R.L of B is more than 100.00 m
97.While doing levelling in undulating terrain, it is preferable to set the level on
one side of the slope
98. If the horizontal distance between the staff point and the point of i observation is d, then the error due to curvature of earth is proportional to
99.Sensitiveness of a level tube is designated by radius of level tube
100. Error due to refraction may not be completely eliminated by reciprocal
levelling , Tilting levels are commonly used for precision work , The last reading of levelling is always a foresight