Basic Civil Engineering Multiple Choice Questions on “Methods of Levelling”.
1. How many methods are used in levelling?
a) 3
b) 2
c) 4
d) 5
Answer: b
Clarification: The 2 methods are the height of instrument method and rise and fall method. These are used to evaluate heights of various points.
2. How many types of levelling are there?
a) 3
b) 2
c) 4
d) 5
Answer: c
Clarification: There are 4 ways to perform levelling. They are direct levelling, trigonometric levelling, barometric levelling and stadia levelling.
3. Trigonometric levelling is also called:
a) Indirect levelling
b) Differential levelling
c) Fly levelling
d) Profile levelling
Answer: a
Clarification: In trigonometric levelling, the horizontal distance and vertical angle are measured from the station to the object. It uses trigonometric relations to compute the vertical height of a point.
4. In _________ levelling, the first and last point are at a far distance.
a) Fly
b) Differential
c) Profile
d) Reciprocal
Answer: b
Clarification: In differential levelling, a number of inter-stations are located and then the instrument is shifted to each station and the elevation is observed.
5. Stadia levelling is a modified form of:
a) Fly levelling
b) Differential levelling
c) Simple levelling
d) Trigonometric levelling
Answer: d
Clarification: Tacheometer principle is used to determine the elevation of points. Line of sight is inclined and it is more suitable for surveying in hilly terrains.
6. The last reading taken from the instrument is called:
a) End sight
b) Free sight
c) Fore sight
d) Back sight
Answer: c
Clarification: Fore sight (FS) is noted as last reading and back sight (BS) is noted as first reading taken from the instrument. Any intermediate points are noted down as intermediate sight (IS).
7. Reciprocal levelling is used when,
a) Flat terrain
b) Obstacles are there
c) BM not visible
d) Highway construction
Answer: b
Clarification: If the points to surveyed lie on opposite banks of a river, reciprocal levelling can be used. It is done from both sides to eliminate chances of error.
8. In a hilly terrain, staff reading is more at:
a) Lower point
b) Higher point
c) First point
d) Last point
Answer: a
Clarification: In hilly terrain, the lowest point will give the highest staff reading. It is at a lower level compared to others and hence has more height.
9. Which is the arithmetic check for the height of instrument method?
a) ∑FS + ∑BS = First RL + Last [email protected]
b) ∑BS – ∑FS = Last RL – First [email protected]
c) ∑FS + ∑BS = Last RL + First [email protected]
d) ∑BS – ∑FS = First RL – Last [email protected]
Answer: b
Clarification: To check if the readings are written properly, an arithmetic check is done. The sum of back sight (BS) and Fore sight (FS) are subtracted. It should be equal to the difference of the last and first reduced level (RL).
10. Which instrument is used in trigonometric levelling?
a) Wye level
b) Compass
c) Theodolite
d) Dumpy level
Answer: c
Clarification: Trigonometric levelling involves measurements that are angular and hence requires an angle measuring instrument, like theodolite.
11. In levelling, error due to earth’s curvature is to be corrected using:
a) Cc=0.0673D2
b) Cc=0.0112D2
c) Cc=0.0136D2
d) Cc=0.0785D2
Answer: d
Clarification: Correction for earth’s curvature and refraction is to be applied. Cc is given by 0.0785D2. Combined correction Cc – Cr is given by 0.0673D2.