The direction of the magnetic meridian is established at each traverse station and the direction of the line is determined with reference to the magnetic meridian. This method of traversing is called
In the loose needle method, the direction of the magnetic meridian is established at each traverse station and the direction of the line is determined with reference to the magnetic meridian. In other words, the magnetic bearing of each line is determined directly. A theodolite fitted with a compass is used for determining the magnetic bearing of the traverse line. The loose needle method is also known as free needle method.
Which one of the following figures indicates the principle of traversing?
The principles of traversing say that, a traverse should consist of a series of straight lines connected together to form an open or a closed polygon. The points, defining the ends of the traverse lines are called traverse stations or traverse points.
If L is the perimeter of a closed traverse, ΔD is the closing error in departure, the correction for the departure of a traverse side of length L1, according to Bowditch rule, is
Correction of departure of a line according to Bowditch Rule =
⇒ = l1 traverse side length
∑l = total traverse side length
∑l = l1 + l2 + l3....
given ∑l = L
∑D = total departure = -[ L1/L x ΔD]
If the coordinates bf A are 100 N and 200 E and those of Care 100 S end 200 E, then the length AC is
Contour interval is
Transit rule of balancing a traverse is applied when
Match List-I with List-II and select the correct answer using the codes given below the lists:
A. Equally spaced contour lines
B. Contours are always perpendicular to
C. Contours increase in elevation from inside to outside
D. Contours with horizontal equivalent zero
1. Steepest slope
2. A vertical cliff
3. A saddle
4. A depression
5. Uniform slope
Equally spaced contour lines are formed by uniform slope.
Contours are always perpendicular to the steepest slope.
A series of closed contours on map indicates a depression, if the higher values are outside.
Contours never run into one another except in the case of a vertical cliff. In the vertical cliff case, several contours coincide at a point and the horizontal equivalent becomes zero.
The contours lines of different elevations can intersect in the case/cases of
1. Vertical diff
3. Over hanging diff
Which of the following methods of contouring is most suitable for a hilly terrain?