WHAT YOU NEED: an orange, pencil and paper. The orange should be as round as possible, so the peel represents the surface area of a sphere. STEP 2: Repeat this 3 more times. You should now have 4 ...

Even from space, you wouldn’t detect something important about Earth’s shape: It’s not perfectly round. It’s actually a ...

For spinning spheres, centrifugal force is maximized at the equator, where the rotational speed is highest. The amount of the force depends on the size of the object and how fast it’s spinning—bigger ...