🔍 Key Concepts

• magnetic dip (inclination) and what it means when dip is zero • difference between an agonic line (zero magnetic variation) and other magnetic lines • the idea of a magnetic equator compared to geographic equator

💭 Think About

• Ask yourself: magnetic dip is related to how the needle tilts up/down; where on Earth would the needle lie perfectly horizontal, with no dip? • Which term refers to lines where compass variation (difference between true and magnetic north) is zero, and which to lines where dip (tilt) is zero? • Do all three listed terms describe the same physical line on Earth, or do they describe different magnetic properties?

✅ Before You Answer

• Be clear on the difference between magnetic variation (declination) and magnetic dip (inclination) before choosing. • Check which choice is specifically defined as the line of zero dip, not just zero variation. • Confirm whether a magnetic meridian is a single great-circle line through the poles or a special line of zero dip.