Question

why is equator known as the great circle ​

Answer 1

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Great circles are seen on all meridians on Earth. All the lines of longitude meet at the poles, intersecting the Earth in half. Thus a great circle always splits the Earth into two halves, so that the Equator is a great circle.

Explanation:

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Answer 2

Explanation:

Great circles are seen on all meridians on Earth. All the lines of longitude meet at the poles, intersecting the Earth in half. Thus a great circle always splits the Earth into two halves, so that the Equator is a great circle.