Surveying Multiple Choice Questions on “Plane Table Surveying Accessories”.
1. Which of the following does not belong to the instruments of plane table?
a) Spirit level
b) Plumb bob
c) Compass
d) Theodolite
Answer: d
Clarification: Spirit level is used for levelling the table at the station point. Plumb bob is used to transfer the point in sheet to the ground. Compass is used to indicate the magnetic north. Theodolite is not used in this case as the entire process is done manually without any instrumental usage.
2. In plane table surveying, plotting and recording of values are done simultaneously.
a) True
b) False
Answer: a
Clarification: Plane table surveying is a graphical method, in which the field observations and plotting process is done simultaneously. It involves making a map in the field while the ground can be seen by the topographer and without intermediate steps of recording in field notes.
3. What are the dimensions of Johnson table?
a) 60*45 cm
b) 45*60 cm
c) 40*60 cm
d) 45*65 cm
Answer: b
Clarification: The Johnson board usually consists of 45*60 cm dimension, which is used while doing important field works which needs precise values.
4. For obtaining high precision values, which among the following is used?
a) Wooden table
b) Johnson table
c) Coast survey table
d) Traverse table
Answer: c
Clarification: Coast survey table can be able to obtain more precise values than the remaining plane tables. Due to more accuracy in levelling, the ability of producing precise values increases.
5. Alidade is used for___________
a) Sighting
b) Levelling
c) Transferring point to ground
d) Drawing lines
Answer: a
Clarification: The presence of eye vane of object vane allows the alidade to bisect the required points which are near by the station.
6. Orientation of table involves which among the following?
a) Traversing
b) Fore sighting
c) Back sighting
d) Measuring bearings
Answer: c
Clarification: Orientation by back sighting is a process that involves setting up of the plane table when there is no possibility over the station mark.
7. Orientation by trough compass is done for obtaining precise values.
a) True
b) False
Answer: b
Clarification: Orientation by trough compass is low accurate method which is done when speed of the work is more important than obtaining accurate values. Orientation by means of back sighting involves in obtaining more precise values.
8. Which of the following indicates the correct set of alidade?
a) Plain, reverse
b) Complex, telescopic
c) Plain, theodolite
d) Plain, telescopic
Answer: d
Clarification: In general, two types of alidades are used. They include plain, telescopic alidades. Now-a-days telescopic alidade is fitted on the plane table which is making the work from complex to simple.
9. By plotting and recording values simultaneously, there is a possibility to occur more errors.
a) True
b) False
Answer: a
Clarification: It might be possible to note the wrong value while processing simultaneously, but it is one of the most accurate methods which gives the best output.
10. In which of the following cases, orientation by back sighting is used?
a) When approximate levelling is required
b) When second point is available for orientation
c) When it is not possible to set instrument over station mark
d) When speed is important than accuracy
Answer: c
Clarification: Orientation by back sighting is used when it is not possible to set instruments over station mark and also for obtaining more precise and accurate values.