Rope Around The Earth Add 1 Meter

The idea is to imagine the earth is a cube or just a square really and ask yourself if you added say 8 feet to the rope how far would that raise it above the square earth.

Rope around the earth add 1 meter.

This string is cut and a piece 1 metre 3 ft 3 in in length is added in. What will its height be above the surface. 15cm that s how far off the ground we re lifting the string remember out of 6 370km is close to one part in forty million. This puzzle is somewhat counter intuitive.

Then imagine placing this longer rope back around the earth s equator. If you have reasoned the answer and can t believe it you are probably right. From the diagram it s pretty clear it s one foot. Now imagine lifting off this very long rope don t ask me how cutting it somewhere so as to stitch into it exactly one meter of extra rope.

How high is that. Suppose you tie a rope tightly around the earth s equator. In a common version of this puzzle string is wrapped around the equator of a perfectly spherical earth. The radius of earth is 6371 km approx.

Divide again by pi to get the earth s radius 6 370km. You add an extra 3 feet to the length. From there it s not hard to believe that adding 3 feet to a rope around the actual earth would raise it almost 6 inches. Imagine a rope that fits snugly all the way around the earth like a ring on a person s finger.

Now let us tie a rope tightly around its equator. In fact this brain teaser requires neither an exact measurement of the earth s circumference which in fact varies by many kilometers depending on which circumference you measure nor even an assumption that the earth has a circular cross sect. Rope around the world you have a piece of rope that just fits around the earth. Now untie the rope and add an extra 1 meter of rope and make it a perfect circle and place it around the.

Now imagine the rope is made just one meter longer and lifted uniformly off the surface until it is once again taught. All around the earth the rope is raised up uniformly as high as is possible to make it tight again.