Describe back sighting method of orientation of plane table surveying.

Describe back sighting method of orientation of plane table surveying.
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1 Answer

Answer :

Backsight method of orientation

1. Assume we have to orient the table at next station ‘B’ represented on paper by point ‘b’.

2.the line ‘ba’ is drawn on previous station ‘A’.

3.the alidade is kept on line ‘ba’ and the table is turned around its vertical axis such a way that line of sight passes through ground station ‘A’.

4. When the plotted line ‘ab’ coincides with line ‘AB’ and table will be oriented.
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List any four accessories required for plane table survey.

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Enlist different accessories of plane table survey with their use.

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State the suitability of plane table survey

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Last Answer : The plane tabling is generally suitable for surveys in which high precision is not required. It is mainly employed for small-scale or medium size mapping.

Write any four advantages of intersection method of plane tabling over radiation method of plane tabling.

Description : Write any four advantages of intersection method of plane tabling over radiation method of plane tabling.

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Compare collimation plane method and rise and fall method of reduction of levels.

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Last Answer : The comparison between collimation plane method and Rise and fall method is given below. Collimation plane method Rise and Fall method 1 1. It is rapid method as it involves few calculations. ... Arithmetic check in this method is ΣBS - ΣFS = ΣRise - ΣFall = Last RL - First RL

Explain with neat sketch the procedure of radiation method of plane tabling.

Description : Explain with neat sketch the procedure of radiation method of plane tabling.

Last Answer : 1. The table is set at suitable station e.g. P from where all stations can be sighted and measured. 2. After centering and leveling, mark station P as P' on sheet. 3. Suppose stations A, B, C, and D are ... marked as pa. 5. Similarly station B, C and D are bisected and marked as b, c and d.

Explain intersection method of plane survey.

Description : Explain intersection method of plane survey.

Last Answer : Intersection method of plane tabling 1. Lay out a base line AB and measure it and Plot a distance ab' on sheet using any scale. 2.Set up instrument at A' with a' over A' 3.Orient the table by ... sighted rays bd, bg, bf, bc are drawn to determine points intersection, d, g, f, c.

Differentiate between plane of collimation and rise and fall method.

Description : Differentiate between plane of collimation and rise and fall method.

Last Answer : S.N Rise and fall method Plane of collimation 1 It is slow and more tedious. It is more rapid and less tedious  2 It is laborious as it involves more calculations. It is simple ... .S.-ΣF.S=ΣRise-Σfall =Last RL-First RL Arithmetical check ΣB.S.- ΣF.S=Last RL-First RL

To orient a plane table at a point roughly south of the mid-point of two inaccessible conical hill stations and in the plains, a point is selected in line with AB and table is oriented at by bringing ab in line with AB. A ray is then drawn towards and at the table is oriented by back ray method. The orientation so obtained, is (A) Unique and correct (B) Incorrect (C) Manifold and correct (D) Not reliable

Description : To orient a plane table at a point roughly south of the mid-point of two inaccessible conical hill stations and in the plains, a point is selected in line with AB and table is oriented at by bringing ab ... , is (A) Unique and correct (B) Incorrect (C) Manifold and correct (D) Not reliable

Last Answer : (C) Manifold and correct

The method generally preferred to for contouring an undulating area, is (A) Chain surveying (B) Plane table surveying (C) Tacheometrical surveying (D) Compass surveying

Description : The method generally preferred to for contouring an undulating area, is (A) Chain surveying (B) Plane table surveying (C) Tacheometrical surveying (D) Compass surveying

Last Answer : (C) Tacheometrical surveying

In a solution of the three-point problem in plane table surveying, the converging of error is attained through : (a) Concyclic concept (b) Bessel’s method (c) Triangle of error (d) Tracing paper method

Description : In a solution of the three-point problem in plane table surveying, the converging of error is attained through : (a) Concyclic concept (b) Bessel’s method (c) Triangle of error (d) Tracing paper method

Last Answer : (c) Triangle of error

Describe stepping method of chaining on sloping ground.

Description : Describe stepping method of chaining on sloping ground.

Last Answer : 1. If A and B are the two points on sloping ground, for which horizontal distance is to be measured. 2. Unfold the chain. By touching handle to station A, stretch it up to maximum possible ... 6. Thus total horizontal distance on sloping ground is calculated as d(AB) = L1+L2+L3 in meters.

Describe method of measuring distances on ground using chain and arrows.

Description : Describe method of measuring distances on ground using chain and arrows.

Last Answer : Method of measuring distances on ground. 1. Mark the position of survey stations whose distance is to be measured using wooden peg. (say A and B) 2. now, ranging is done if distance ... station B. Thus total horizontal distance will be equal to addition of distances measured of each parts.

Enlist the methods of plane tabling.

Description : Enlist the methods of plane tabling. 

Last Answer : Method of Surveying with the plane table are : 1) Radiation 2) Intersection 3) Traversing 4) Resection

Differentiate between plane and geodetic survey on any four points.

Description : Differentiate between plane and geodetic survey on any four points. 

Last Answer : Difference between Plane Surveying and Geodetic Surveying Points Plane Surveying Geodetic Surveying Definition Plane surveying is that type of surveying in which mean surface of ... Traditional survey equipment is used Precise and modern survey equipment are required

What are the sources of errors in plane tabling?

Description : What are the sources of errors in plane tabling?

Last Answer : The following are the sources of errors in plane tabling 1) The board not being horizontal 2) The table not being accurately centered 3) The table not being Correctly oriented 4) The objects ... through the station point 7) Inaccuracy in plotting 8) The expansion and contraction of the paper 

The operation of resection involves the following steps 1. Rough orientation of the plane table 2. The three lines form a triangle of error 3. Drawing lines back through the three control points 4. Select a point in the triangle of error such that each ray is equally rotated either clockwise or anti clockwise 5. The points obtained by three rays are the correct location. The correct sequence is (A) 1, 3, 2, 4, 5 (B) 1, 2, 3, 4, 5 (C) 1, 4, 3, 2, 5 (D) 1, 3, 2, 4, 5

Description : The operation of resection involves the following steps 1. Rough orientation of the plane table 2. The three lines form a triangle of error 3. Drawing lines back through the three control points 4. Select a point in the triangle of error ... 2, 3, 4, 5 (C) 1, 4, 3, 2, 5 (D) 1, 3, 2, 4, 5

Last Answer : (A) 1, 3, 2, 4, 5