Deck 7: Surveying and Contouring Techniques

Question 1

Which of the following errors can be neutralised by setting the level midway between the two stations ?

A)error due to curvature only
B)error due to refraction only
C)error due to both curvature and re-fraction
D)none of the above

Answer 1

error due to both curvature and re-fraction

Question 2

Height of instrument method of levelling is

A)more accurate than rise and fall method
B)less accurate than rise and fall method
C)quicker and less tedious for large number of intermediate sights
D)none of the above

Answer 2

quicker and less tedious for large number of intermediate sights

Question 3

The rise and fall method

A)is less.accurate than height of instrument method
B)is not suitable for levelling with tilting levels
C)provides a check on the reduction of intermediate point levels
D)quicker and less tedious for large number of intermediate sights

Answer 3

provides a check on the reduction of intermediate point levels

Question 4

If the staff is not held vertical at a level¬ling station, the reduced level calculated from the observation would be

A)true R.L.
B)more than true R.L.
C)less than true R.L.
D)none of the above

Question 5

The difference between a level line and a horizontal line is that

A)level line is a curved line while hori-zontal line is a straight line
B)level line is normal to plumb line while horizontal line may not be normal to plumb line at the tangent point to level line
C)horizontal line is normal to plumb line while level line may not be normal to the plumb line
D)both are same

Question 6

The sensitivity of a bubble tube can be increased by

A)increasing the diameter of the tube
B)decreasing the length of bubble
C)increasing the viscosity of liquid
D)decreasing the radius of curvature of tube

Question 7

With the rise of temperature, the sensitivity of a bubble tube

A)decreases
B)increases
C)remains unaffected
D)none of the above

Question 8

Refraction correction

A)completely eliminates curvature correction
B)partially eliminates curvature correction
C)adds to the curvature correction
D)has no effect on curvature correction

Question 9

The R.L, of the point A which is on the floor is 100 m and back sight reading on A is 2.45° m. If the foresight reading on the point B which is on the ceiling is 2.74° m, the R.L. of point B will be

A)94.80 m
B)99.71 m
C)100.29 m
D)105.20 m

Question 10

As applied to staff readings, the corrections for curvature and refraction are respectively The above table shows a part of a level field book. The value of X should be

A)98.70
B)100.00
C)102.30
D)103.30

Question 11

Sensitiveness of a level tube is designated by

A)radius of level tube
B)length of level tube
C)length of bubble of level tube
D)none of the above

Question 12

Which of the following statements is in-correct ?

A)Error due to refraction may not be completely eliminated by reciprocal levelling.
B)Tilting levels are commonly used for precision work.
C)The last reading of levelling is always a foresight.
D)All of the above statements are incorrect.

Question 13

Dumpy level is most suitable when

A)the instrument is to be shifted frequently
B)fly levelling is being done over long distance
C)many readings are to be taken from a single setting of the instrument
D)all of the above

Question 14

The difference of levels between two stations A and B is to be determined. For best results, the instrument station should be

A)equidistant from A and B
B)closer to the higher station
C)closer to the lower station
D)as far as possible from the line AB

Question 15

Contour interval is

A)inversely proportional to the scale of the map
B)directly proportional to the flatness of ground
C)larger for accurate works
D)larger if the time available is more

Question 16

An imaginary line lying throughout the surface of ground and preserving a constant inclination to the horizontal is known as

A)contour line
B)horizontal equivalent
C)contour interval
D)contour gradient

Question 17

The suitable contour interval for a map with scale 1 : 10000 is

A)2 m
B)5m
C)10 m
D)20 m

Question 18

Select the correct statement.

A)A contour is not necessarily a closed curve.
B)A contour represents a ridge line if the concave side of lower value con¬tour lies towards the higher value contour.
C)Two contours of different elevations do not cross each other except in case of an overhanging cliff.
D)All of the above statements are correct.

Question 19

A series of closely spaced contour lines represents a

A)steep slope
B)gentle slope
C)uniform slope
D)plane surface

Question 20

Direct method of contouring is

A)a quick method
B)adopted for large surveys only
C)most accurate method
D)suitable for hilly terrains

Question 21

In direct method of contouring, the process of locating or identifying points lying on a contour is called

A)ranging
B)centring
C)horizontal control
D)vertical control

Question 22

In the cross-section method of indirect contouring, the spacing of cross-sections depends upon
i. contour interval
ii. scale of plan
iii. characteristics of ground
The correct answer is

A)only (i)
B)(i)and(ii)
C)(ii) and (iii)
D)(i), (ii) and (iii)

Question 23

74°Which of the following methods of con-touring is most suitable for a hilly terrain ?

A)direct method
B)square method
C)cross-sections method
D)tacheometric method

Question 24

75°Select the correct statement.

A)Contour interval on any map is kept constant.
B)Direct method of contouring is cheaper than indirect method.
C)Inter-visibility of points on a contour map cannot be ascertained.
D)Slope of a hill cannot be determined with the help of contours.