What do isogonic lines on a chart indicate?

Question 1 of 2707066636ee928f7522a1c519a1f

Back

Question 1 of 27070

Q

What do isogonic lines on a chart indicate?

🔍 Key Concepts

• Magnetic variation on nautical charts • Difference between isogonic and agonic lines • How the earth’s magnetic field affects a compass

💭 Think About

• Ask yourself: when navigating with a magnetic compass, what chart information helps you correct the compass reading to true north? • Which choice describes a line that connects many places on the Earth that all share the same magnetic property? • Look at the word structure: what might the prefix in isogonic suggest about what is the same along the line?

✅ Before You Answer

• Verify which option describes equality of a magnetic property over an area, not just a single point • Distinguish between a line of zero variation and a line of equal (non‑zero) variation • Confirm that dip and magnetic latitude are different concepts from variation shown on most navigation charts