the shortest way to get from one location on earth to another
All parallels of latitude, except for the Equator, are not great circles. Great circles are the largest circles that can be drawn on a sphere and pass through its center, whereas small circles do not pass through the center of the sphere.
No; neither of the tropics is a great circle. The only line of latitude that is a great circle is the equator. The arctic and antarctic circles are not great circles, either.
Because they make big circles around the Earth.
Because any 'Great Circle' is the shortest distance across a sphere. Where the Earth is concerned , all the meridians and the Equator are Great Circles. The Plane of a 'Great Circles ' 'cut' the sphere into two equally sized hemispheres. NB Other than the Equator all the latitudes are NOT great Circles.
There are an infinite number. If you draw two great circles, no matter how close together they are, I can always draw a great circle ... or 2 or 3 or 10 ... between them.
No, not all parallels are great circles. A great circle is the largest possible circle that can be drawn on a sphere, and it divides the sphere into two equal hemispheres. Parallels, or lines of latitude, are circles that run parallel to the equator, and only the equator itself is a great circle. Other parallels, such as those near the poles, are smaller circles and do not divide the sphere into equal halves.
Great circles.
great circles
great circles
Yes, there are great circles on Earth that are entirely in water, such as the Equator or the Prime Meridian. These circles divide the Earth into two equal halves and are significant in navigation and geographical reference.
great circles
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