Traverse Coordinates – Sign Convention for Total Latitude of a Point In traverse computations, the total latitude (algebraic north–south displacement) of a point is taken as positive under which positional condition relative to the reference parallel?
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AWhen the point lies north of the reference parallel (northing)
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BWhen the point lies south of the reference parallel (southing)
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CWhen the point lies east of the reference parallel
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DWhen the point lies west of the reference parallel
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EWhen the point lies exactly on the reference meridian only
Answer
Correct Answer: When the point lies north of the reference parallel (northing)
Explanation
Introduction:Traverse closure and coordinate computations use latitudes (north–south components) and departures (east–west components). A consistent sign convention is vital for balancing and plotting. This question checks the standard algebraic sign of latitude for a point's position.
Given Data / Assumptions:
- Latitude is the projection along the meridian (N–S axis).
- Departure is the projection along the east–west axis.
- Reference parallel/meridian define the coordinate origin or baseline.
Concept / Approach:
By convention in surveying, northings are positive and southings are negative. Hence, any net displacement north of the reference parallel yields a positive total latitude. Eastings are positive departures; westings are negative, but these affect departure, not latitude.
Step-by-Step Solution:
Resolve each traverse leg into latitude L * cos θ (with sign by quadrant).Sum latitudes algebraically to get total latitude of a point.Interpret sign: positive sum implies the point is north of the reference parallel.Therefore select option (a).Verification / Alternative check:
Check a simple case: a single northward leg yields positive latitude; a southward leg yields negative—consistent with convention across textbooks and practice.
Why Other Options Are Wrong:
(b) reverses the sign; (c) and (d) refer to departures, not latitudes; (e) is unrelated to the sign definition.
Common Pitfalls:
Confusing latitude with departure; mixing local grid conventions with geodetic signs—always confirm the project standard.
Final Answer:
When the point lies north of the reference parallel (northing)