1.14.5. Local attraction

Try these first

1. 1.

   What is local attraction in surveying?

   Hint

   Think about what might interfere with a compass reading.

2. 2.

   Name two objects that can cause local attraction.

   Hint

   Consider common materials found in construction or around buildings.

3. 3.

   What does local attraction refer to in surveying?

   • Disturbance from nearby objects
   • Magnetic north direction
   • Surveying instruments

   Hint

   Think about what nearby elements could interfere with compass accuracy.

4. 4.

   True or False: The fore bearing and back bearing of a line should ideally differ by 180°.

   • True
   • False

   Hint

   Recall the purpose of measuring both bearings.

5. 5.

   You have a surveying site where local attraction is suspected due to nearby steel structures. After measuring, the fore bearing is 230° and the back bearing is found to be 30°. Compute the degree of error and suggest a plan to mitigate future inaccuracies.

   Hint

   Understand the relationship between fore and back bearing and what they're supposed to sum to.

6. 6.

   In a previous survey, a team recorded many local attractions which resulted in discrepancies. Discuss the importance of educating all team members about identifying and handling local attraction.

   Hint

   Consider the importance of communication and training in technical fields.