Define close traverse. Why checks are necessary in closed traverse

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## Closed Traverse

Definition (1 mark)

A closed traverse is a type of traverse in which the series of survey lines forms a closed polygon, either by returning to the starting point or by closing on another known point.

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Why Checks are Necessary in Closed Traverse (2.5–3 marks)

Checks are necessary in a closed traverse for the following reasons:

1. Detection of Errors

• Helps to identify errors in angle and distance measurements.

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2. Angular Check

• The sum of interior angles should satisfy the condition:

  (2n - 4) \times 90^\circ \quad \text{(for n sides)}

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3. Linear (Closing) Check

• The traverse should close properly, meaning the final point should coincide with the starting point.
• Any gap is called closing error.

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4. Accuracy Verification

• Ensures that the survey work is reliable and accurate.

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5. Adjustment of Errors

• Errors can be distributed and corrected using methods like Bowditch rule.

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Key Concept

• A closed traverse allows both angular and linear checks, which are not possible in open traverse.

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Conclusion (1 mark)

Checks are essential in a closed traverse to detect, evaluate, and adjust errors, ensuring accuracy and reliability of the survey results.

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