The Earth S Magnetic Field

Step 1: Understanding Magnetic Inclination
Magnetic inclination, also called magnetic dip, refers to the angle between the Earth's magnetic field lines and the horizontal plane at a given location.
The symbol is used to represent the magnetic inclination in geomagnetic studies.
At the magnetic poles, the inclination is 90°, while at the magnetic equator, the inclination is 0°.
Step 2: Why Other Options are Incorrect
Option (a) is incorrect because the horizontal component refers to the part of the magnetic field that lies in the horizontal plane, which is not denoted by .
Option (b) is incorrect because the magnetic meridian refers to the line connecting the magnetic poles and is not denoted by .
Option (c) is incorrect because magnetic declination refers to the angle between the magnetic meridian and the true north, and is not represented by .
Step 3: Conclusion
Thus, denotes magnetic inclination, which is the angle between the magnetic field lines and the horizontal plane.