## Theodolite Surveying Viva Questions

Theodolite Surveying Viva Questions

1. What you know about axis of the bubble tube?

Axis of the bubble tube it is the straight line that is tangential to the longitudinal curve open of the level tube at its centre.

2. Explain line of collimation?

Line of collimation can be defined as the line passing through the intersection of the horizontal and vertical cross hairs and the optical centre of the object glass and its continuation.

3. What is the optical axis of the telescope?

Optical axis of the telescope is the line passing through the optical centre of the IPC and the optical centre of the object glass and its continuation.

4. What is transiting?

The telescope is turned in vertical plane through 180 degree about the trunnion axis and the process is called transiting.

5. When the telescope is said to be normal?

If face of the vertical circle is to the left of observer and the level tube is attached to the telescope, then the telescope is said to be normal.

6. Name the axis, in which the telescope and the vertical circle of the theodolite rotate in a vertical plane?

Trunnion axis

7. What is the traverse deflection of angle?

The traverse deflection of angle is the difference between the included angle and 1800.

8. In which traversing, the included angles are measured by setting the vernier near to zero and reads both Vernier on back station?

In precision traverse

9. How will you measure the included angles of a theodolite traversing?

Clockwise direction from the back station

10. Which method is preferred for observing and included angle with better accuracy than what is achievable by a vernier?

Repetition method.

11. Which error varies with the direction of pointing and inversely with the length of sight?

Centering error of a theodolite.

12. In horizontal angles, which type of error is large for steeply inclined sights?

The error due to imperfect leveling of the plate bubble.

13. What can be achieved by focusing the objective and the eyepiece?

Removal of parallax

14. What type of errors affects the precision of a theodolite traverse in ordinary conditions?

Systematic linear errors

15. When angles from two transit stations are preferred?

If a distant object visible from two transit stations are located, angles from two transit stations are preferred

16. What is the reliable method of plotting a theodolite traverse?

By independent coordinates of each station.

17. What is latitude to the leg?

It is the orthographical projection of a traverse leg upon the reference meridian.

18. What is called as the total latitude?

Total latitude is the co-ordinate of a point measured perpendicular to the parallel. If the total positive of a point lies north of the reference parallel then it is said to be positive.

19. How the latitude of a traverse leg is obtained?

By multiplying cosine of its reduced bearing.

20. How balancing the traverse is done if the angular measurements of a traverse are more precise than its linear measurements?

By transit rule

21. How the length of a traverse leg is obtained?

Multiply the latitude and secant of its reduced bearing

22. How we can eliminate the error due to defective graduation's on the graduated horizontal circle of a theodolite?

This can be eliminated by taking the mean of several readings distributed over to different portions of the graduated circle.

23. While traversing, directly or indirectly the measurements are made in the field, these measurements are?

Linear and angular

24. If the length of a line is multiplied by sine of its reduced the length, what is obtained?

The departure of a line

25. Name the instrument with is used for accurately measuring the horizontal and vertical angles?

Theodolite

In a vertical plane, if the telescope of a theodolite can revolve through a complete revolution about its it horizontal axis then it is known as transit theodolite.

27. What is the use of theodolite in surveying?

For finding angles between two lines, finding difference in elevation and prolonging survey line.

28. How the size of a theodolite is fixed?

By measuring diameter of the graduated circle of lower plate.

29. Mention the uses of theodolite?

Finding difference in the elevation, for tunnel aligning and highway ranging.

30.  How the permanent adjustment of the theodolite is attained?

By the elimination of parallax and by the adjustment of vertical circle index.

31. How the line of sight of theodolite is adjusted?

By Spire test

32. What are the type of errors eliminated my face left and face right observations?

Eccentricity type errors

33. How the latitude coordinates and departure coordinates are related?

latitude coordinates - North and South &

departure coordinates - East and West

34. What you know about consecutive consecutive co-ordinates?

Consecutive coordinates are the latitude and departure of a station with respect to the preceding station.

35. What type of methods are adopted for balancing consecutive coordinates of a theodolite traverse?

Transit method, Axis method and Bowditch method.

36. Where the cross hairs are fitted in the surveying telescopes?

In front of the  eyepiece

37. In the surveying telescope diaphragm is nearer to the eyepiece?

True

38. Real and inverted images are formed by the objective in the plane of crosshairs?

True

39. Name the axis in which the telescope can be rotated in the horizontal plane?

Vertical axis

40. The parallax should be removed if the image formed by the objective is not situated in the plane of crosshairs?

True

41. The eye-piece should be focused when the crosshairs are not visible clearly?

True

42. What is the definition of a telescope?

The definition of a telescope is the capacity of producing a sharp image.

43. What you know about the magnification of a telescope?

The magnification of a telescope is the ratio of focal length of the objective to that of the eyepiece.

44. What you know about the resolving power of a telescope?

Resolving power of a telescope is the power to form distinguishable images of objects separated by small angular distance.

45. For the accurate measurement of horizontal angle than a Vernier, which method is used?

Repetition method

46. What you know about the deflection angle?

Deflection angle is the angle made by a survey line with the prolongation of the p the proceeding line.

47. What is the range of deflection angle?

The deflection angle may take any values between 0 degree and 180 degree.

48. What is a direct angle in surveying?

The direct angle may be measured clockwise from the proceeding survey line to the following survey line.

49. What is the range of direct angle?

The direct angle may take any values between 0 degree and 360 degree.

50. How Vertical angle is measured?

The Vertical angle can be measured between the inclined line of sight and the horizontal.

51. Where are the applications of traversing by the method of deflection angles?

In Highways, railways and canals.

52. Shifting center is an arrangement provided in theodolite?

True

53. What are the parts included in the levelling head of a transit theodolite?

Parallel plates, Levelling screws and a tribrach plate.

54. What is a scale plate?

A scale plate is the outer spindle attached to the lower plate in a transit theodolite.

55. The upper plate is attached to the inner spindle and is called the Vernier plate?

True

56. The upper plate is also known as alidade of theodolite?

True

57. The upper plate has 2 Vernier 180 degrees apart for reading the horizontal angles?

True

58. What are the functions of a levelling head?

The leveling head is mainly used to attached the theodolite to the tripod, for providing a bearer for the outer hollow spindle and for providing a mean of levelling the instrument.

59. How the theodolite rotates, when the upper clamp screw is unbolt and the lower clamp screw is stiffened?

When the lower clamp screw is stiffened and upper clamp screw is unbolt, the theodolite rotates on its inner spindle with relative motion between the graduated scale of lower plate and Vernier.

60. How you can eliminate the error due to eccentricity of inner and Outer axis?

This can be eliminated by reading both Vernier and taking the mean of the two observations.

61. How the error due to line of collimation not being perpendicular to horizontal axis is eliminated?

This can be eliminated by taking the mean of both face observations.

62. What is the maximum limit of the closing error in a closed traverse?

The maximum limit is √N x least count of instrument

63. What is Relative closing error?

Relative closing error     =   (Closing error) / (Perimeter of the Traverse)

64. What you know about traverse base?

It is the distance between terminal points computed from a subsidiary traverse run between them.

65. What is the direction of closing error, if L is the latitude and D is the departure?

tan Î¸ = ∑D / ∑L

66. What happens to the deflection angle, if the included angle is greater than 180 degrees?

The deflection angle should be right handed or positive.

## Plane Table Surveying Viva Questions

Plane Table Surveying Viva Questions

1. What you know about plane table?

Basically plane table can be defined as an instrument, which is used for surveying by a graphical method. In plane table, the field work and plotting are done simultaneously. Plane tabling is widely used in small and medium scale mapping. Parallelism is the principle used in plane table surveying. Teak or pine is used for making the plane table.

2. Name the instrument that is used for plotting the directions?

3.  How we can measure the elevation of the points of observation?

Cartographic surveying is the graphical method, which is used for producing topographic maps.

5. How the board of plane table is fitted?

By levelling head, Ball and socket arrangement.

6. In what names the bevelled edge of the alidade is known?

Working edge, Ruling edge and Fiducial edge.

7. What is the length of an alidade?

50 cm

8. What is the metal used for the making of alidade?

Brass or Gunmetal

9. What are the components in telescopic alidade?

Vertical circle, cross hairs and level tube

10. How magnetic north is marked in plane tabling?

By Trough compass

11. What is the use of plumbing fork or U-frame?

Centering

12. For what purpose, spirit level is used?

Levelling

13. For work in climates in, which type of sheets are commonly used?

Zinc for Celluloid

14. What you know about orientation?

Keeping table in the position parallel to its earlier position is known as orientation.

15. What is the use of radiation in surveying?

For the survey of small areas, which can be commended from a single station, radiation method is used.

16. Which method is used for locating the distance in accessible points, the broken boundaries and rivers?

Intersection

17. Which method is used for the checking of distant objects?

Intersection method

18. For locating the topographical details, the plane tabling used for running survey Lines between stations that are previously located by other methods of surveying. The method is known as?

Traversing

19. Which method is used for establishing the instrumentation?

Resection

20. Explain about two point problem?

Basically the orientation of a plane table with two inaccessible points is termed as the two point problem.

Observe two well defined the points, that are visible from the instrument station and their positions are already plotted on the plan. Now locating the position on the plan of the station occupied by the plane table is known as two point problem.

21. What you know about three point problem?

By the observation of three well defined points, locating the position of instrument stations is known as three point problem. The three point problem can be resolved by mechanical method, trial and error method and graphical method. Trial and error method is the accurate method used in three point problem.

22. What is the maximum limit of error due to inaccurate centering?

m/40

23. What is the limit of precision in plotting?

0.025 cm

24. What will do at the time of the orientation of a plane table?

The previous station is sighted when the plane table is oriented.

25. How we can locate a mosque, if it is situated on the far side of a river and is inaccessible?

By intersection

26. Is plane table survey best for temperature country?

Yes

27. A for a large scale survey, whether the accurate centering of the plane table is needed?

Yes

28. Whether checks can be applied to the work in the office in a plane tabling?

No

29. What is the use of large scale maps in surveying?

For the accurate centering in plane table.

30. In what condition the three point the problem fails?

When and instrument station lies on the ortho centre of the great triangle, the three point the problem fails.

31. For built up area, plane tabling for filling in details is suited- True or false?

False

32. For equatorial countries, plane tabling is most suited - True or false?

False

33. For small scale mapping, the exact orientation is more important in plane tabling than accurate centering?

True

34. In a plane table survey, centering and orientation are interrelated?

True

35. For large scale mapping, the exact centering of a plane table is essential?

True

36. For good inter visibility countries, plane table survey is used?

True

37. By the orientation of a small scale map, centering of plane table cannot be sacrificed?

False

38.  An alidade is also known as?

Sight Rule

39. Is U-Frame applicable for the orientation in the plane table?

NO

40. For medium scale mapping, accurate entering is used?

False

41. No special care in the fixing on the ground is required if the drawing sheet is used in plotting a plane table survey?

True

42. For a built up area, the radiation method is most suited?

False

43. How the accurate orientation of plane table is achieved if the plotted position of an instrument station is not known?

By observing three well defined points

44. How is it possible to go one of the plotted stations in the method of resection?

By a back ray

45. What is Lehman's rule?

While looking towards the station the plane table location to be fixed is always to the left or right opposite of the rays.

46. Plane table is more stable than theodolite?

False

47. For accurately locating the points, a theodolite is better than a plane table?

True

48. By using which method, the contour maps can be speedily prepared?

By a plane table, contour maps can be prepared speedily than theodolite stadia method.

49. How the error occurred in small scale mapping by plane table?

By inaccurate centering

50. What you understand about strength of fix?

It is the accuracy of the establishment of the instrument station.

51. If the plane table station is taken on the circumference of great circle then it strength of fix is?

52. If the plane table station is taken inside the great circle then it's strength of fix is?

Good

53. How the field book is ignored in surveying?

By plane table survey

54. Field work and office work are done in sequences in?

Plane table survey

55. Which method must be used in a plane survey?

Orientation

56. In plane tabling, intersection is also known as graphic triangulation?

True

57. The two point problem is quicker than the three point problem?

True

58. When the resented position of the plane table station from three known position is unreliable?

When the station lies on the circumference of circumscribing circle

59. In setting up of plane table, centering and levelling are simultaneously done?

True

## Chain Surveying Viva Questions

Chain Survey Viva Questions

1. Which line is baseline in the layout of survey?

The longest main survey line is the baseline in the layout of the chain survey

2. What is the length of long offsets in Chain surveying?

More than 15 meters

3. If a 20 m tape held 40mm out of the line, what is the resulting error per tape length?

4mm

4. What is a check line?

The Check line can be defined as the line joining the apex of a triangle to some fixed point on the opposite side.

5. What you know about Tie line?

The line joining some fixed points on the main survey line is known as Tie line. The Tie line in a chain survey enables the surveyor for locating the interior details far away from the main chain lines.

6. In Chain survey, which line fix up the directions of all other lines?

The baseline

7. What are the uses of a Plumb bob?

Main use of a plumb bob is the measuring distances along slopes in a hilly country. It is also used for testing the verticality of ranging poles and also used for activate centering of a theodolite over a station mark.

8. In which situations chain surveying is most suited?

Chain surveying is mostly used when the surveying area is small, the plans are required on a large scale and the ground is fairly level and open with simple details.

9. What is the minimum angle level in a well conditioned Triangle?

30 degrees

10. Which line checks the accuracy of the framework in a chain survey?

The check line

11. What is the limiting length open the upset when it's perpendicular direction is set out by an eye?

15 m

12. For locating a point by oblique offset, what is the  minimum number of  distances to be measured?

At least two distances

13. What are the factors on which the accuracy in laying down and measuring of the perpendicular offsets depends?

Scale of plotting, Length of offset and importance of the object.

14. What is the use of oblique offsets?

For accurately fixing the position of a point, it must be located by oblique offsets.

15. Which factor limit the field work in Chain surveying?

Linear measurements

16. Whether the general layout of the chain lines depend the accuracy of measurement in the chain surveying?

No

17.   Weather the limiting length often Oxford depends on the indefinite features to be surveyed?

No

18. How the baseline is measured?

By chain

19. The distance measured along a chain line is called?

Chainage

20. What are the factors depending the limiting length of an offset?

The nature of the ground, the desired accuracy and the scale of plotting.

21. What is is the angle bye French cross staff?

45 or 90 degrees.

22. What is used for setting out of long offsets?

Open cross staff

23. In an optical square, what is the angle of intersection of horizon mirror and index mirror?

45 degrees

24. Compare optical square and Prism square?

The working principle of both the optical square and prism square are same. In a prism square, since the angle between the reflecting mirrors is fixed no adjustment  is required.

25. Which land feature is an obstacle to chaining and not in ranging?

Rivers

26.  Which land feature is an obstacle to ranging and not in chaining?

Hills and Buildings

27. What is is the first step taken in chain survey execution?

Reconnaissance

28. What is the basic principle of  optical square?

Double reflection

29. A field is measured with a 1.0 percent too long chain is 10,000 acres. What is the the correct area of the field?

10,201 acres

30. What instrument is used for the measurement of angles?

Sextant

31. Which instrument is used for setting out an offset at right angle?

Open cross staff

32. In which angle, the adjustable cross staff is used for setting out an offset?

At any angle

33. Half silvered and half un silvered glass in an optical square is?

The index glass

34. Which glass in an optical square is wholly silvered ?

The index glass

35. What are the instruments belongs to a class of reflecting instruments?

Line Ranger, box sextant and prismatic compass

36. What is the angle between the first incident ray and the last reflected ray in an optical square?

90°

37. What is the angle between the reflecting surfaces of a prism square?

45 degrees

38. Is it possible to set offset correctly on both sides, if the chain line run a noun north south direction is horizontal and the ground in east West direction is slopping?

Yes

39. What is an equilateral triangle?

It is the best shape Triangle to be used in triangulation so that the distortion due to errors in measurement and potting is minimum.

40. What you know about Tie stations?

The main survey lines have subsidiary stations known as tie stations. Tie lines are lines which joins the tie stations. In the chain survey map these lines are mainly taken to fix the directions. In Chain surveying these lines are also taken to form chain angles where triangulation is impossible.

## Soil Mechanics Viva Questions

Soil Mechanics Viva Questions

1. Compare Alluvial Soil and Aeolian Soil?

The soils that are transported by running water is known as alluvial soil and the soil transported by wind is termed as Aeolian soil.

These type of soils are deposited at the bottom of the lakes.

Note: Soils can be derived from igneous rocks, sedimentary rocks and metamorphic rocks. The chemical weathering of soil is mainly due to oxidation, hydration, carbonation and leaching. We can say the residual soils are sands, silts and clays. Sands are the examples of cohesion less soils. A fine grained soil may or may not be plastic in nature. We know that 0.002 mm is the maximum size of the particles of a clay.

1. In which format, the each decimal digit is expressed in a Binary Coded Decimal (BCD) number?

In a BCD system, each decimal digit is represented by Bits.

2. What is the earliest calculating device?

Abacus

3. Discuss about first, second, third and fourth generation computers?

Vacuum tubes are used in the first generation computers. From year 1940 to 1955, first generation computers are commonly used. The second generation computers are used from 1955 to 1965 and the technology used is transistor technology. In third generation, Integrated chips (IC) are used and is from 1965 to 1971. The fourth generation computers uses Very Large Scale Technology (VLSI) an is common from 1971 onwards.

4. What is machine language?

The binary system uses only two symbols (o and 1). The language written in the form of binary number system (in the form of 0's and 1's)  is known as binary system.

5. Discuss about compiler (interpreter), assembly language and algorithm?

A compiler or interpreter is a program that is used to translate a high level language program into the machine language (0 and 1). The assembly language is a low level language used by alphabets used  as machine language. The purpose of an assembler is to translate this language to machine language. We can define Algorithm as a series of step by step instructions to perform a particular task.