Could you crawl under it?
A length of wire completely surrounds the earth at the Equator. Imagine that the wire floats, that it has negligible mass, and that it fits snugly around the earth. Cut the wire and splice in an extra 20 feet of wire. Now the wire will be slightly slack in its fit. Raise the wire equally at all points away from the earth until it is tight again. A. How high will the wire be off the earth at all points?(in ft. to 3 decimal places)
The answer is 3.183.
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1 solution
This applies also to any object with circular bases. Lets say a certain scaled Globe has a circumference of 40 in in the equator So, 40 = 2(pi)(r) And then, we add 20 in its circumference: So, 40+20 = 2(pi)(r)
The question is to find the height of the newly adjusted circumference at ALL points of the equator, since the new height at all points must be equal, we therefore solve for the difference in their radii.
Solution r = 60/2pi -40/2pi = 3.183098862 inches.
The radius difference is still the same even if you changed the values of the circumference as long as the difference of their circumference is 20 in.
In this problem, the answer is 3.183098862 feet. Technically, I can crawl in it, haha. But I can't walk around the circumference, since i'm 5.5 feet. Hahaha