In bearings how do we draw an angle O from A?For e.g to draw the bearing A from O we use the clockwise direction. What direction is adopted for this drawing?Please explain in detail
Bearing is an angle measured from the meridian (the North South line) to the line. In sketching bearing follow these steps:
1. Draw the meridian. It should be a vertical line on your paper. The upper end will be denoted as the North and the lower end is denoted as the South.
2. Draw a line perpendicular to the meridian line (horizontal line). We will call this as the East-West line with the right end denoted as East and the left end denoted as the West. Notice we have formed a system similar to the rectangular coordinate system. The 1st quadrant being the NE quadrant; the 2nd quadrant will be the NW quadrant; the 3rd is the SW quadrant; and the 4th as the SE quadrant.
3. Now draw a line starting from the origin (the intersection of the meridian and the East-West line) towards any direction you want and call this as line L. The angle between the meridian and L is the value of the bearing, which is measured from the meridian to the L either clockwise or counterclockwise direction depending on which quadrant the L is drawn. Note the value of the angle cannot be greater than 90°
Suppose line L1 is drawn in the 1st quadrant or the NE quadrant, then the angle is measured from the meridian in clockwise direction to line L1. If the value of the angle is 30° then the bearing of line L1 is 30°NE or N30°E. Now if another line L2 is drawn in the 2nd quadrant or the NW quadrant, then the angle is measured from the meridian in counterclockwise direction to line L2 If the value of the angle is 45° then the bearing of line L2 is 45°NW or N30°W. In cases where the line is drawn in the 3rd or SW quadrant and 4th quadrant or SE quadrant, the angle will be measured in clockwise and counterclockwise direction respectively from the meridian to the line.
The bearing is used to describe direction. It becomes meaningless if expressed without the name of the quadrant attached to it.
What if the value of the angle is 0° or 90°?
When the value of the angle is 0° then the direction of the line is either North or South and when the value of the angle is 90° then the direction of the line is either East or West. Here we will omit the value and label the bearing as either due N, due S, due E or due W.
Furthermore do not fuse Bearing and Whole Circle Bearing in case you will encounter the latter someday. Whole Circle Bearing is commonly known as Azimuth and is another different concept.