Compass bearings – definition of reduced bearing (RB) Reduced bearing of a line is the angle between which two directions under the quadrantal (NE, SE, SW, NW) system?

Introduction / Context:
Bearings can be expressed as whole-circle bearings (0°–360°) or reduced (quadrantal) bearings. Reduced bearing specifies direction by an acute angle with respect to the nearer part of the meridian, along with the quadrant (NE, SE, SW, NW). This question checks the precise geometric definition of reduced bearing used in field notes and plotting.

Given Data / Assumptions:

• The meridian is the N–S line through the station.
• We use the quadrantal system with angles 0°–90° plus quadrant letters.
• Angle is always the acute angle to the nearer meridian end.

Concept / Approach:

Reduced bearing (RB) is defined as the acute angle between the given line and the part of the meridian that lies closer to it—either the north end or the south end. The notation includes the quadrant (e.g., N 30° E). This distinguishes RB from whole-circle bearings that measure clockwise from the north through 360°.

Step-by-Step Solution:

Verification / Alternative check:

Conversion formulas between WCB and RB confirm this definition: RB = min(θ, 180°−θ) with quadrant given by θ.

Why Other Options Are Wrong:

Options A and B describe one-directional clockwise/anticlockwise measures used in WCB, not RB.

Option C references east/west; in RB we reference the meridian (N or S), not the parallel.

Common Pitfalls:

Measuring RB from the east/west line; forgetting to add the correct quadrant letters; confusing acute RB with obtuse WCB values.

Final Answer:

The given line and that part of the meridian (N end or S end) lying adjacent to it