20-01-26 Surveyor - Plane Table - Part 4

Which of the following pairs correctly categorizes the methods of plane tabling based on their primary purpose?

• Plotting Details: Traversing & Radiation; Establishing Stations: Intersection & Resection
• Plotting Details: Radiation & Intersection; Establishing Stations: Traversing & Resection
• Plotting Details: Resection & Intersection; Establishing Stations: Traversing & Radiation
• Plotting Details: Traversing & Resection; Establishing Stations: Radiation & Intersection

Answer explanation

Radiation and Intersection are used for plotting details, while Traversing and Resection are used for establishing instrument stations.

Assertion: The Intersection method is also known as Graphical Triangulation and is preferred for hilly terrain. Reason: The object position is obtained by intersection of rays without measuring object distance.

• Both A and R are true and R explains A
• Both A and R are true but R does not explain A
• A is true but R is false
• A is false but R is true

Answer explanation

Intersection uses graphical triangulation and avoids distance measurement to inaccessible objects, making it suitable for hilly terrain.

In plane table traversing, which statement regarding orientation is incorrect?

• Backsighting is more accurate than compass orientation
• Orientation aligns ground and map features
• Trough compass eliminates local attraction errors
• Orientation mistakes cause major plane table errors

Answer explanation

Trough compass orientation may cause errors due to local attraction.

Which statements about the Radiation method are correct? 1. Best for small areas 2. Measures baseline only 3. Slow for many details

• 1 and 2 only
• 2 and 3 only
• 1 and 3 only
• 1, 2 and 3

Answer explanation

Radiation requires distance to every point, making it slow when many details are involved.

You need to extend an existing survey map but your instrument station is not plotted. Which method is used?

• Traversing
• Radiation
• Intersection
• Resection

Answer explanation

Resection is used to locate the instrument position on the map when it is unknown.

Assertion: Resection is used for plotting area details. Reason: It determines the plotted position of the instrument station.

• Both A and R are true and R explains A
• Both A and R are true but R does not explain A
• A is true but R is false
• A is false but R is true

Answer explanation

Resection is used for establishing station position, not for plotting details.

What is the unique advantage of the Intersection method over Radiation?

• Covers large areas by moving stations
• Eliminates distance measurement to object
• Uses rays from single station
• Uses three point problem

Answer explanation

Intersection requires only baseline measurement and avoids object distance measurement.

To plot a church spire across a river where chaining is impossible, which method and measurement is correct?

• Radiation and distance to spire
• Intersection and baseline length
• Traversing and backsight distance
• Resection with no measurement

Answer explanation

Intersection is ideal for inaccessible objects and requires measuring only the baseline.

In plane table surveying, which method is MOST appropriate when new stations must be fixed successively to cover a large area?

• Radiation

• Intersection

• Traversing

• Resection

Answer explanation

Traversing is used when the survey area is large and the plane table has to be shifted from one station to another to establish successive stations.

Two-point and three-point problems are associated with which plane tabling method?

• Intersection
• Traversing
• Resection
• Radiation

Answer explanation

Two-point and three-point problems are standard procedures in the resection method.