Define true bearing and magnetic bearing.

Define true bearing and magnetic bearing.
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1 Answer

Answer :

1. True bearing – (i) The angle between true meridian or geographical north and any line known as true bearing.

2.Magnetic bearing-(i)The angle between magnetic meridian and any line is known as magnetic bearing.


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Related questions

Define the terms - dip of needle, magnetic bearing, fore bearing and back bearing.

Description : Define the terms - dip of needle, magnetic bearing, fore bearing and back bearing.

Last Answer : Dip of needle: It is downward inclination or small angle made by freely suspended magnetic needle with the horizontal. Magnetic bearing: Magnetic bearing of a survey line is the horizontal angle ... of line measured in backward direction or opposite direction of survey, is known as back bearing.

Define: WCB and Quadrantal Bearing system

Description : Define: WCB and Quadrantal Bearing system

Last Answer : Ans.: 1)WCB:-In this system the bearing of a line is always measured clockwise for the north point of the reference meridian towards the line round the circle the angle thus measured is called ... the bearing of a line is measured clockwise from the north point or south point whichever is nearest .

Define the terms i) Fore Bearing, ii) Open traverse, iii) Closing error, iv) Reduced bearing

Description : Define the terms i) Fore Bearing, ii) Open traverse, iii) Closing error, iv) Reduced bearing

Last Answer : i) Fore bearing : The bearing observed in the direction of progress of survey in clockwise manner is called fore bearing  ii) Open traverse : When the first and last survey lines does ... north or south direction in clockwise or anticlockwise manner is known as reduced or quadrantal bearing. 

Define- 1. Whole circle bearing 2. Reduced bearing 3. Fore bearing 4. Back bearing

Description : Define- 1. Whole circle bearing 2. Reduced bearing 3. Fore bearing 4. Back bearing

Last Answer : 1.Whole circle bearing-  The bearing measures only in the clockwise direction from meridian or north direction is known as whole circle bearing. 2.Reduced bearing  The bearing measures with ... bearing  The bearing observed in the direction of opposite of survey is called fore bearing. 

Define: i) W.C.B. ii) Reduced Bearing

Description : Define: i) W.C.B. ii) Reduced Bearing

Last Answer : i)Whole circle bearing: The bearing measures only in the clockwise direction from meridian or north direction is known as whole circle bearing.   ii) Reduced bearing: The bearing measured ... north or south direction in clockwise or anticlockwise manner is known as reduced or quadrant bearing 

Define ‘ Fore bearing ’ & ‘ back bearing ’ of line with a neat sketch

Description : Define ‘ Fore bearing ’ & ‘ back bearing ’ of line with a neat sketch

Last Answer : Fore bearing : The bearing of line observed in the direction of progress of survey is called fore bearing of the line. Bearing of line AB is observed at A' towards B' is called as fore bearing of the line ... The bearing observed at B' towards A' is called as back bearing of the line AB'  

Define: (i) True meridian (ii) Magnetic meridian

Description : Define: (i) True meridian (ii) Magnetic meridian

Last Answer : i. True meridian: It is line of intersection of plane passing through North Pole, South Pole and point under consideration.  ii. Magnetic meridian: Magnetic meridian at point is direction shown by freely suspended magnetic needle at that point.

Define : i) Traversing ii) Magnetic Meridian

Description : Define : i) Traversing ii) Magnetic Meridian

Last Answer : i) Traversing : Traversing is the series of survey lines connecting successive established traverse stations along the route of survey  ii) Magnetic Meridian : The direction indicated by ... and properly balanced Magnetic needle unaffected by local attractive force is called magnetic meridian.

Describe quadrantal bearing system. State the purpose it is used.

Description : Describe quadrantal bearing system. State the purpose it is used. 

Last Answer : Quadrantal Bearing - 1. The magnetic bearing of line measured clockwise or anticlockwise from north or south pole whichever is nearer. 2. These bearings are also called as reduced bearings. 3. ... lines in a closed traverse. 2. It is used to calculate back bearing for respective quadrants.

With neat sketch, write the procedure of measurement of fore bearing with compass.

Description : With neat sketch, write the procedure of measurement of fore bearing with compass.

Last Answer : For measuring fore bearing of line AB, i) Place the compass over station A, center and level it.  ii) Looking through eye slit towards object vane, bisect the ranging rod at station ... which coincides with horse hair at observer end. The observed reading is the fore bearing of line AB

Find the back bearing of the following lines having fore bearing as given below: (i) PQ = N 55° 0' E (ii) EF == 280° 0' (iii) CD = S 58° 30' W (iv) OM= 180° 0'

Description : Find the back bearing of the following lines having fore bearing as given below: (i) PQ = N 55° 0' E (ii) EF == 280° 0' (iii) CD = S 58° 30' W (iv) OM= 180° 0'

Last Answer : i) F.B OF PQ = N 55°0 ’ E  B.B Of PQ = S 55°0 ’W  ii) F.B. Of EF = 280°0 ’   B.B OF EF = F.B -180°= 280°0 ’ -180° = 100°0 ’  iii) F.B OF CD = S 58°30’W  B.B OF CD = N 58°30’ E  iv) F.B OF GH = 180°  B.B OF GH = F.B -180°=180°-180°= 0°

Differentiate between reduced bearing and whole circle bearing

Description : Differentiate between reduced bearing and whole circle bearing

Last Answer : Quadrantal Bearing/Reduced Bearing Whole Circle Bearing The horizontal angle made by a line with the magnetic north or south (whichever is closer from the line) in the eastward or westward direction ... from 0° to 90°  The value of the whole circle bearing varies from 0° to 360° 

Explain dip of magnetic needle with neat sketch.

Description : Explain dip of magnetic needle with neat sketch. 

Last Answer : i) The inclination of the magnetic needle with the horizontal is called as magnetic dip of the needle. ii) Ordinary needle if perfectly balanced on pivot, remains in horizontal position. But when the needle ... sliding weight is attached on the side of the needle which is at higher position.  

Explain ‘Declination of Magnetic needle’ and types of declination.

Description : Explain ‘Declination of Magnetic needle’ and types of declination. 

Last Answer : Ans: The magnetic meridian at a place does not coincide with the true meridian at that place. The horizontal angle made by the magnetic meridian with the true meridian is called magnetic declination'. ... in others it points to the west of the true meridian called as West declination'

What is mean by magnetic declination?

Description : What is mean by magnetic declination?

Last Answer : Magnetic declination- It is the deviation or shifting magnetic needle from true or geographical north direction, hence the horizontal angle made by magnetic north with true north direction is known as Magnetic declination.

Explain the terms magnetic declination and dip of needle.

Description : Explain the terms magnetic declination and dip of needle.

Last Answer : Magnetic Declination: The horizontal angle between the magnetic meridian and true meridian is known as magnetic declination. When the north end of magnetic needle is pointed towards west side of ... needle is deflected downwards and southern hemisphere south end of the needle is deflected downwards.

Define fly leveling and profile leveling

Description : Define fly leveling and profile leveling

Last Answer : Fly Leveling adopted to transfer bench marks from one place to other .In this leveling only FS & BS are taken.  Profile leveling:- The operation in which the object is to determine the ... known distanced apart along a given line to obtained the accurate outline of the surface of the ground 

Define : 1) Bench mark 2) Datum surface 3) Line of collimation 4) Change Point

Description : Define : 1) Bench mark 2) Datum surface 3) Line of collimation 4) Change Point 

Last Answer : 1) Bench mark: - It is a fixed reference point of known elevation.. 2)Datum surface :-It is any arbitrarily assumed level surface from which vertical distance are measured 3) Line of collimation:- ... which the fore and back sights are taken.  It is the point denoting the shifting of the level.

Define orientation. State two methods of orientation. Which method is most accurate and why?

Description : Define orientation. State two methods of orientation. Which method is most accurate and why? 

Last Answer : Orientation is the process of keeping plane table in same position as that is occupied in previous station. Methods of orientation: i) Magnetic meridian method using trough compass ii) Back ... and not by using trough compass. Therefore there is no error occurring due to local attraction.

Define Dip and deflection of needle.

Description : Define Dip and deflection of needle.

Last Answer : Dip of the magnetic needle: It is the upward or downward movement of magnetic needle in vertical plane due to earth's gravitational force is known as dip of needle. Deflection of needle : ... west direction, that horizontal angle between magnetic and true north is said to be declination of needle.

Define Change point and its necessity in leveling.

Description : Define Change point and its necessity in leveling.

Last Answer : Change point : It is the point at which both backsight and foresight readings are taken before and after shifting the level instrument. Necessity of change point in leveling : It is ... observations from single station due to large area, abrupt ground level variation and unavoidable obstruction. 

Define horizontal line and vertical line.

Description : Define horizontal line and vertical line.

Last Answer : Horizontal line : A straight line tangential to the level line and perpendicular to the plumb line is called horizontal line.  Vertical line : A line perpendicular to horizontal line and coinciding plumb line is known as vertical line

Define local attraction. State two causes of local attraction.

Description : Define local attraction. State two causes of local attraction.

Last Answer : Local attraction: It is the deviation or deflection of magnetic needle from its normal position under influence of external magnetic forces is called as local attraction. Causes of local attraction : 1. Iron ... structure 2. Electric cable line 3. High voltage current 4. Bunch of key 5. Steel Tape 

Define surveying.

Description : Define surveying.

Last Answer : Surveying- It is branch of civil engineering in which relative positions of ground points are determined by taking linear and angular measurement.

Define- 1. Datum 2. Change point

Description : Define- 1. Datum 2. Change point

Last Answer : 1. Datum- It is the imaginary level surface or level line from which the vertical distance of different points are measured.  2. Change point- It is the point at which both back sight and foresight readings are taken before and after shifting the level instrument. 

Define surveying & state its objectives

Description : Define surveying & state its objectives

Last Answer : Surveying- It is branch of civil engineering in which relative positions of ground points are determined by taking linear and angular measurement. Objectives: 1. To determine the relative positions of ... quantities 4. To prepare a topographical map showing details of hills, valleys and rivers.

Define: i) Level Line, ii) Horizontal Line, iii) Vertical Line iv) Bench Mark.

Description : Define: i) Level Line, ii) Horizontal Line, iii) Vertical Line iv) Bench Mark. 

Last Answer : j) Level Line: It is line lying in a level surface; it is therefore, normal to the plumb line at all points. ii) Horizontal Line: It is a straight line tangential to the level line at a ... RL determined with reference to the datum line. They serve as reference points for finding RL of new points. 

Define orientation and principle of plane tabling.

Description : Define orientation and principle of plane tabling. 

Last Answer : Orientation: The orientation of plane table means keeping the plane table at all stations parallel to the position it occupied at first station. Principles of plane table survey: 1. The rays drawn from ... same as that of previous station i.e. orientation should be done at each changed station.  

Define base line and check line with neat sketch.

Description : Define base line and check line with neat sketch. 

Last Answer : 1)Base Line : The longest line running roughly through the middle of the area to be surveyed is known as base line 2) Check line: The line joining the apex of a triangle to some fixed point on the ... A line joining some fixed point on any two sides of a triangle is known as check line. 

Define: i) Mean sea level, ii) Station point.

Description : Define: i) Mean sea level, ii) Station point. 

Last Answer : i) M.S.L: Mean sea level is the average height of the sea for all stages of tides. It is determined by averaging the hourly tide heights over a long period of 19 years at a place.  ii) Station ... is a point which is to be established at a given elevation or it is a point where the Staff is held 

Define: i) Open Traverse ii) Closed Traverse.

Description : Define: i) Open Traverse ii) Closed Traverse. 

Last Answer : i) Open traverse: When the first and last survey lines does not meets at common point and hence does not form a closed polygon, then it is said to be open traverse.  ii) Closed Traverse: When last and first survey stations meet at common point, traverse is called as closed traverse.

Define the terms - Foresight, back sight, intermediate sight and change point.

Description : Define the terms - Foresight, back sight, intermediate sight and change point.

Last Answer : 1. Fore sight: It is the last staff reading from any set up of the leveling instrument and indicates the shifting of the instrument or end of leveling work. 2. Back sight: It is the first staff reading ... point fore sight is taken from one set up and a back sight is taken from the nest set up. 

State any four types of offsets and define them.

Description : State any four types of offsets and define them. 

Last Answer : i) Long offset: If length of offset more than 15 m. ii) Short offset: If length of offset less than 15 m. iii) Perpendicular offset: Offset taken perpendicular to chain line. iv) Oblique offset: Offset not taken perpendicular to chain line.

Define the term – base line and check line.

Description : Define the term – base line and check line.

Last Answer : Base line: Base line is generally the longest line running roughly through the middle of the area. It is laid on a level ground as far as possible. The whole frame work is built upon this line. ... point on the opposite side or a line joining some fixed point on any two sides of the triangle.

Define the term: (1) Level surface (2) Line of collimation

Description : Define the term: (1) Level surface (2) Line of collimation

Last Answer : Level surface: It is a surface parallel to the mean spheroidal surface of the earth. It is normal to the direction of plumb line at all points. The surface of still water is an example of level ... to the optical center of object glass and its continuation. It is also called as line of sight. 

Define the following: (i) Height of instrument (i) Back sight (iii) Fore sight (iv) Axis of bubble tube

Description : Define the following: (i) Height of instrument (i) Back sight (iii) Fore sight (iv) Axis of bubble tube

Last Answer : i. Height of instrument: It is the reduced level of line of collimation when the leveling instrument is properly leveled. It is obtained by adding the BS reading to RL of bench mark or change point on which the ... when the bubble is at the center of its run i.e. at middle point of the tube.

Define the following terms: (i) Level surface {ii) Datum line (iii) Reduced level (iv) Axis of telescope

Description : Define the following terms: (i) Level surface {ii) Datum line (iii) Reduced level (iv) Axis of telescope

Last Answer : i)Level Surface : Any surface is parallel to mean spheroidal surface of earth is said to be a level surface. The water surface of still lake is also considered to be level surface. ii) ... an imaginary line passing through the optical Centre of object glass and optical Centre of the eye piece.

Define Local attraction.

Description : Define Local attraction.

Last Answer : Local attraction – when magnetic needle does not remain in N-S direction due to effect of magnetic substances present around the compass, such error at station is known as local attraction. 

Define: (i) Long offset (ii) Short offset

Description : Define: (i) Long offset (ii) Short offset

Last Answer : i. Long offset: The offset whose length is more than 15 m. ii. Short offset: The offset whose length is less than or equal to 15 m.

Define Ranging. State types of ranging.

Description : Define Ranging. State types of ranging.

Last Answer : Ranging: It is process of locating points on ground along straight line. Types of ranging: 1. Direct ranging. 2. Indirect ranging

Define bench mark and enlist the types of bench mark.

Description : Define bench mark and enlist the types of bench mark.

Last Answer : It is fixed reference point of known or assumed elevation. It is used either as a starting point for levelling or as a check while closing. There are four kinds of bench marks. i. Great ... ) bench mark. ii. Permanent bench mark. iii. Arbitrary bench mark. iv. Temporary bench mark.

Define : 1) Change point 2) Height of instrument.

Description : Define : 1) Change point 2) Height of instrument.

Last Answer : 1) Change point It is point on which fore and back sights are taken. 2) Height of instrument. It is the reduced level of line of collimation when the leveling instrument is properly leveled. It is ... adding the BS reading to RL of bench mark or change point on which the staff reading was taken.

Define leveling.

Description : Define leveling.

Last Answer : Levelling is an ‘art of determining relative heights or elevations of different points on the earth’s surface so that the same may be represented on a plan or map’. It is essentially a process dealing with the measurements in vertical plane.

Define 1)Ranging 2)Chaining

Description : Define 1)Ranging 2)Chaining

Last Answer : 1) Ranging The method of establishing intermediate points on a straight line between the two fixed points is known as ranging. 2)Chaining The method of measuring the distance with the chain or tape is called as Chaining.

A 20m chain was found to be 6cm too long after chaining a distance of 1059m. It was found to be 9cm too short after chaining at the end 1985m. If the chain was correct before commencement of work find the true distance.

Description : A 20m chain was found to be 6cm too long after chaining a distance of 1059m. It was found to be 9cm too short after chaining at the end 1985m. If the chain was correct before commencement of work find the true distance.

Last Answer : Given : Line ABC, AB=1059m, AC=1985m  L= 20m, No error at start, 0.06m too long at B,  0.09m too short  Find : True distance of AC = ? Solution : For part AB L = Length of chain= 20 m e = Average ... Total true distance of AC = True distance of (AB + BC)  = 1060.59 m + 922.52 m  = 1983.11 m

A 20 m chain was found to be 10 cm too short after chaining 1000 m It was found to be 20 cm too short after chaining 1800 m. If the chain was correct before commencement of the work find the true distance.

Description : A 20 m chain was found to be 10 cm too short after chaining 1000 m It was found to be 20 cm too short after chaining 1800 m. If the chain was correct before commencement of the work find the true distance.  

Last Answer : Average error in chain for 1000 m length = (0 + 10) / 2 = 5 cm = 0.05 m too short True length up to 1000 m = (20 - 0.05) x 1000 / 20 = 997.5 m. Average error in chain from 1000 m to 1800 m length = (10 ... 1800 m length = (20 - 0.15) x 800 / 20 = 794.0 m. True distance = 997.5 + 794 = 1791.5 m.

The length of line measured with a chain was found to be 250m. Calculate the true length of line if i) The length was measured with 30 m chain and the chain was 10cm too long and ii) The length of chain was 30 m in the beginning and 30.10 m at the end of the work.

Description : The length of line measured with a chain was found to be 250m. Calculate the true length of line if i) The length was measured with 30 m chain and the chain was 10cm too long and ii) The length of chain was 30 m in the beginning and 30.10 m at the end of the work. 

Last Answer : Given Data: L = 30 m Measured Length = 250 m Solution: Case i) The length was measured with 30 m chain and the chain was 10cm too long L' = 30 + 0.1 = 30.1 m Correct Distance = (L'/L) x Measured Length ... = 30.05 m Correct Distance = (L'/L) x Measured Length  = (30.05/30) x 250  = 250.42 m

What is changing face

Description : As used in survey

Last Answer : It's the operation of changing the face of telescope from left to right and vice versa.

The process of surveying is therefore in three stages namely:

Description : The process of surveying is therefore in three stages namely:

Last Answer : (i) Taking a general view This part of the definition is important as it indicates the need to obtain an overall picture of what is required before any type of survey work is undertaken. In ... of quantities, datasheets, drawings and in land surveying maps and plan showing the features on the land.

Tacheometric Surveying

Description : Tacheometric Surveying

Last Answer : Tacheometric is a branch of surveying in which horizontal and vertical distances are determined by taking angular observation with an instrument known as a tachometer. Tacheometric surveying is adopted in rough ... be prepared for investigation works within a short time on the basis of such survey.