Explain the terms magnetic declination and dip of needle.

Explain the terms magnetic declination and dip of needle.
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1 Answer

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 true meridian, the position is termed Declination West (θW). When the north end of magnetic needle is pointed towards east side of true meridian, the position is termed Declination East (θE).

Dip of needle. If the needle is perfectly balanced before magnetization, it does not remain in the balanced position after it is magnetized .This is due to the magnetic influence of the earth. The needle is found to be inclined towards the pole. This inclination of needle with the horizontal is known as deep of needle. The amount of deep of needle is not constants but it varies from place to place, in northern hemisphere north end of the needle is deflected downwards and southern hemisphere south end of the needle is deflected downwards.
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Description : Explain four types of meridians. 

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Explain reciprocal ranging with neat sketch.

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Description : Explain Direct method of chaining on sloping ground with neat skeetch. 

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Description : Explain Graphical adjustment of closing error in a closed traverse.  

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Last Answer : 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 placing alidade ... the case of the survey of mountainous country. 5. The only linear measurement required is that of a base line.

Explain Procedure for chain and compass traversing.

Description : Explain Procedure for chain and compass traversing.

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Explain Fly Levelling with neat sketch. State situation under which fly levelling is needed.

Description : Explain Fly Levelling with neat sketch. State situation under which fly levelling is needed.

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Description : Explain Orientation of plane table by Back-sighting Method.

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Explain principle of chain surveying

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Explain indirect ranging with neat sketch

Description : Explain indirect ranging with neat sketch

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Explain the procedure of profile leveling for construction of road.

Description : Explain the procedure of profile leveling for construction of road.

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State and explain temporary adjustments of dumpy level.

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