The upper vertex of a great circle track is...

Question 1 of 2707066636ee928f7522a1c51a526

The upper vertex of a great circle track is in LONG 156°00'E. Sailing eastward, the great circle track will cross the equator in which LONG?

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Question 1 of 27070

The upper vertex of a great circle track is in LONG 156°00'E. Sailing eastward, the great circle track will cross the equator in which LONG?

🔍 Key Concepts

• Relationship between a great circle’s upper vertex longitude and the longitudes where it crosses the equator • Symmetry of a great circle track about its highest latitude (vertex) when sailing east–west • How longitudes are measured east and west of the Prime Meridian (0°) and how to convert between °E and °W

💭 Think About

• Sketch the globe with the equator, the meridians, and mark the vertex at 156°E; then think about how the great circle must curve when you sail eastward from that vertex toward the equator • Ask yourself: for a great circle that reaches its maximum latitude at 156°E, will the equator crossing be east or west of 156°E when you continue eastward? • Compare how far each answer choice is from the opposite side of the globe (180°) relative to 156°E, and consider which side (E or W) should match the geometry of the great circle

✅ Before You Answer

• Verify how many degrees of longitude separate 156°E from 180° (the antimeridian) and which direction (east or west) that difference lies • Confirm that when converting between E and W, you are always measuring from the Prime Meridian and that 180°E is the same line as 180°W • Check that the chosen longitude is consistent with the idea that the great circle is symmetric about the meridian passing through its upper vertex