Question

A bearing of a line is also known as:
1. reduced bearing 
2. true bearing 
3. magnetic bearing
4. azimuth

Answer 1

Correct Answer - Option 3 : magnetic bearing

Explanation:

Bearing: It is angle which a line makes with the reference line / meridian. There are two types of bearings:

1. True bearing: 

• It is the horizontal angle which the line makes with the true meridian.
• Since true meridian doesn't change with time and thus true bearing remains constant.
• The true bearing of a line is also called as azimuth.
• It is measured from the north in clockwise direction.
• It is determined from astronomical observations.

2. Magnetic bearing:

• It is the horizontal angle which the line makes with the magnetic north.
• Since magnetic meridian  changes gradually with time and thus magnetic bearing also changes.
• So in general bearing of a line is called magnetic bearing.
• It is determined from either Prismatic Compass (WCB) or Surveyor Compass (QB).