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Unit 4 :- Obstacle in Chaining Numerical

1. P and Q are two points 367 m apart on the same bank of a river. The bearings of a tree on the other bank observed from P & Q are N36°25’E & N40°35’W, respectively. Find the width of the river if the bearings of PQ are S86°35’E.

2. P and Q are two points 367 m apart on the same bank of a river. The bearing of a tree on the opposite bank from P and Q are N30°E and N60°W respectively. Find the width of the river if the bearings of PQ are S86°35’E.

3.  A pond obstructs the chain line AB. Two lines AP and AQ are so chosen that APQ circumscribe the obstacles, and PBQ are on the same straight line. Find the distance AB when the measurements AP = 802 m, AQ = 100 m, PB = 451 m, and BQ = 501 m are given.

 4. A river is flowing from west to east. Two points, P and Q, are selected on the southern bank of the river such that the distance PQ is 100 meters. Point P is westwards. The bearings of a tree R on the northern bank are observed to be 38° and 338° respectively from points P and Q. Calculate the width of the river.

5. A survey line ABC crosses a river flowing from east to west. Points B and C represent the near and far bank of the river, respectively. A perpendicular BD, 50 meters long, is set out at B on the left side of line ABC. The bearings of DC and DA are given as 35°25’ and 125°25’ respectively. The chainages of points A and B are provided as 862 meters and 900 meters respectively. Find the chainage of point C.

6. Points A and B are two points 455 meters apart on the same banks of a river. The bearings of a pole on the other bank from A and B are N30°E and N60°W respectively. Find the width of the river.

7. A survey line ABC crosses a river, with points A and C being on the near and opposite banks respectively. A perpendicular AD, 40 meters long, is set out at A. The bearings of line AD and DC are 38°45’ and 278°45’ respectively. Find the width of the river.

8. A survey line ABC crosses a river, with points A and C being on the near and opposite banks respectively. A perpendicular BD, 50 meters long, is set out at the left side of the line. If the bearing of line DC is 35°24’ and the bearing of line DA is 125°25’, find the chainage of point C.

9.  A pond obstructs the chain line AB. Two lines AP and AQ are chosen such that APQ circumscribes the obstacles, and PBQ are on the same straight line. We are given the following measurements:

AP = 802 m
AQ = 100 m
PB = 451 m
BQ = 501 m
The task is to find the distance AB.

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