Magnetism & Compass 04 Flashcards
1
Q
There are irregularities and fluctuations in the earth’s magnetic field. True or False?
A
True.
2
Q
What is variation?
A
The angular difference (expressed in degrees, minutes and seconds) between true north and magnetic north as measured by a magnetic compass at a particular location on the surface of the earth.
3
Q
What are isogonals?
A
Lines across a map joining points of equal variation
4
Q
What is deviation?
A
The error induced in a compass by local magnetic fields; creating compass north.
5
Q
What causes compass north?
A
Caused my the a/c’s metallic structure and rotating parts(generating their own magnetic field).
6
Q
In what 2 ways are is magnetic variation shown?
A
1) marginal diagram
2) double compass rose