Civil Engineering - Surveying - Discussion

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 is theQuadrantal Bearing or Reduced Bearing of the line.

In quadrantal bearing or reduced bearing, both north and south are considered as reference meridians. Depending upon the position of a survey line, the direction of the reference meridian to the line can be either clockwise or anticlockwise. In the expression of the reduced bearing value of a line, quadrant has to be mentioned in which the line lies.

Please anyone explain the correct answers.

For whole circle Bearing:

BB = FB +-180.
BB = FB +180 (LESS THAN 180).
BB = FB -180 ( MORE THAN 180).

FOR QB SYSTEM:

BB = FB (BUT ONLY DIRECTION CHANGE).
N - S.
S - N.
E - W.
W - E.

Please explain the answer in detail.

@Sandeep.

It is quadrant bearing. Not a wcb.

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 is the Quadrantal Bearing or Reduced Bearing of the line.

SO option C (changing the cardinal points, i.e. substituting N for S and E for W and vice-versa) is right

Please explain it briefly.

In WCB, back bearing is obtained by BB=FB + or - 180, where subtraction is done when FB is more and addition is done when FB is less than 180.

In Reduced bearing system, or Quadrantal bearing system the numerical are same but the letters are put opposite.

C is not the correct answer because quadrantal bearing taking with respect north or south only.