A plane perpendicular to the polar axis will...

🔍 Key Concepts

• Polar axis and Earth's rotation – understand what the polar axis is and how planes can be oriented relative to it • Great circles vs small circles – know the definitions and how they relate to the Earth's center and axis • Relationship between equator, meridians, and the polar axis – which ones are perpendicular, which are parallel, and which intersect at the poles

💭 Think About

• Visualize the Earth as a sphere with a line through the North and South Poles (the polar axis). If you slice the Earth with a plane that is at a 90° angle to that axis, what kind of circle do you get on the surface? • Ask yourself: which lines on Earth pass through the poles, and which lie halfway between them? Which of those are formed by planes through the Earth's center, and which are not? • Think about whether a plane that is always perpendicular to the polar axis could ever produce a line that reaches the poles. Which of the listed options reach the poles, and which do not?

✅ Before You Answer

• Be clear on the definition: a great circle is formed by a plane that passes through the Earth’s center; a small circle is formed by a plane that does not pass through the center • Recall that meridians run from pole to pole along planes that contain the polar axis, not planes perpendicular to it • Confirm that the equator is a special great circle whose plane is perpendicular to the polar axis and passes through the Earth’s center

A plane perpendicular to the polar axis will never form what line on the Earth's surface?

Meridian

Equator

Small circle

Great circle

🔍 Key Concepts

💭 Think About

✅ Before You Answer