1.14.4. Magnetic declination

Try these first

1. 1.

   What is magnetic declination?

   Hint

   Think about how we measure direction using a compass.

2. 2.

   What do you add to the magnetic bearings when there is eastern declination?

   Hint

   Remember that eastern declination is a positive angle.

3. 3.

   What does magnetic declination represent?

   • The difference between true north and magnetic north
   • The average direction of the north pole
   • An angle that remains constant

   Hint

   Focus on its definition regarding direction.

4. 4.

   A compass shows magnetic north. If magnetic declination is +8°, what should you do to find true north?

   • Add 8°
   • Subtract 8°

   Hint

   Think about the position of magnetic north relative to true north.

5. 5.

   A surveyor measures a magnetic bearing of 150°. The magnetic declination at the site is found to be -12°. Calculate the true bearing and justify your answer.

   Hint

   Consider how the negative declination impacts your calculation.

6. 6.

   During a survey, the team encounters unexpected local attractions, altering their readings. Discuss the steps they should follow to ensure accurate measurements despite these influences.

   Hint

   Think about how surveyors verify the consistency of their measurements in practice.