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

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

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 staff reading was taken.

ii. Back sight: It is the first staff reading taken in any set up of the instrument after the leveling has been perfectly done. It is always taken on a point of known RL i.e. on bench mark or change point.

iii. Fore sight: It is the last staff reading in any set up of instrument and indicates the shifting of the level or end of the leveling work.

iv. Axis of bubble tube: It is an imaginary line tangential to the longitudinal curve of the bubble tube when the bubble is at the center of its run i.e. at middle point of the tube.


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Define: WCB and Quadrantal Bearing system

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Define Dip and deflection of needle.

Description : Define Dip and deflection of needle.

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Description : Define Change point and its necessity in leveling.

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Description : Define horizontal line and vertical line.

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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 : i) Traversing ii) Magnetic Meridian

Description : Define : i) Traversing ii) Magnetic Meridian

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Define true bearing and magnetic bearing.

Description : Define true bearing and magnetic bearing.

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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

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Define surveying & state its objectives

Description : Define surveying & state its objectives

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Define orientation and principle of plane tabling.

Description : Define orientation and principle of plane tabling. 

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Define base line and check line with neat sketch.

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

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

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

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

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Define: i) Open Traverse ii) Closed Traverse.

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

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