What is mean by magnetic declination?

What is mean by magnetic declination?
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2 Answers

Answer :

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 as magnetic declination.

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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.
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Related questions

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

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Description : Define true bearing and magnetic bearing.

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Explain dip of magnetic needle with neat sketch.

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

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

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What is the magnetic declination for Seattle?

Description : What is the magnetic declination for Seattle?

Last Answer : '+15° 45'

What is the magnetic declination for vermont?

Description : What is the magnetic declination for vermont?

Last Answer : Need answer

The angle between the magnetic meridian and the geographical meridian at a place is (1) Azimuth (2) Dip (3) Declination (4) Latitude

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The horizontal angle between true meridian and magnetic meridian, is known (A) Bearing (B) Magnetic declination (C) Dip (D) Convergence

Description : The horizontal angle between true meridian and magnetic meridian, is known  (A) Bearing  (B) Magnetic declination( C) Dip (D) Convergence

Last Answer : (B) Magnetic declination

The magnetic bearing of a line is 32° and the magnetic declination is 10° 15' W. The true bearing is (A) 21° 45' (B) 42° 15' (C) 42° 15' W (D) 21° 45' W

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Last Answer : (A) 21° 45' 

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Description : Magnetic declination at any place (A) Remains constant (B) Does not remain constant (C) Fluctuates (D) Changes abruptly

Last Answer : (B) Does not remain constant

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Description : Diurnal variation of magnetic declination is (A) Greater at equator than nearer the poles (B) Less at equator than nearer the poles (C) Less in summer than in winter (D) Same at all latitudes and during different months

Last Answer : (B) Less at equator than nearer the poles

Imaginary line passing through points having equal magnetic declination is termed as (A) Isogon (B) Agonic line (C) Isoclinic line (D) None of these

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Whole circle bearing of a line is preferred to a quadrantal bearing merely because (A) Bearing is not completely specified by an angle (B) Bearing is completely specified by an angle (C) Sign of the correction of magnetic declination is different in different quadrants (D) Its Trigonometrical values may be extracted from ordinary tables easily

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Last Answer : (D) All the above

The vertical angle between longitudinal axis of a freely suspended magnetic needle and a horizontal line at its pivot, is known (A) Declination (B) Azimuth (C) Dip (D) Bearing

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Last Answer : (C) Dip

Which of the following terms is used to describe the angular difference between TRUE north and magnetic north on a topographic map? Is it: w) Magnetic field x) Magnetic intensity y) Magnetic inclination z) Magnetic declination

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Tacheometric Surveying

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What consideration would you have while selecting survey stations and survey lines in a chain survey?

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State the situation where plane table is suitable.

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Description : Define: WCB and Quadrantal Bearing system

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Write errors in leveling and corresponding precaution

Description : Write errors in leveling and corresponding precaution

Last Answer : i) Instrument error with respect to bubble tube, leveling staff. 1.If bubble tube is sluggish it may apparently be in the center though the bubble line is not horizontal. Precaution - ... reading. Precaution- Leveling should be properly done by bringing the bubble of bubble tube at Centre.

State the important points kept in mind while recording the staff readings in level pages with respect first reading, intermediate reading, last reading, change point, carry forward from one page to next page-Remark

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State the purposes of following methods of leveling. i)Profile leveling, ii)Fly leveling, iii)Check leveling iv)Reciprocal leveling

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Draw a sketch and explain how to find height of chajja or slab using dumpy level.

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Explain temporary adjustment.

Description : Explain temporary adjustment.

Last Answer : 1) Place the telescope parallel to foot screw (fig. a) 2) Bring the bubble at Centre by moving foot screw inward or outward simultaneously. 3) Then turn the telescope through 900 so that it ... 6) Once both positions give centered bubble, leveling of instrument is said to be completed.

State fundamental lines and their relationships with each other of dumpy level.

Description : State fundamental lines and their relationships with each other of dumpy level.

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State advantages of plane table survey one each with respect to booking and suitability

Description : State advantages of plane table survey one each with respect to booking and suitability

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State two advantages of telescopic alidade over simple alidade.

Description : State two advantages of telescopic alidade over simple alidade.

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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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Description : Draw sketch and explain method of traversing of plane table surveying. 

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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.

Why zero is marked at south end on a graduated circle of prismatic compass?

Description : Why zero is marked at south end on a graduated circle of prismatic compass?

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State temporary adjustments of prismatic compass

Description : State temporary adjustments of prismatic compass

Last Answer : a) Setting the prismatic compass over prefixed survey station b) Centering the compass over nail point of station using plumb bob c) Leveling of compass in horizontal plane using level tube d) Focusing of prism by raising and lowering the focussing stud

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

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