SOLUTION: Suppose a wire is stretched tightly around Earth. (The radius of Earth is approximately 6400Km). Then suppose the wire is cut and its length is increased by 20 km. It is then place

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Question 346000: Suppose a wire is stretched tightly around Earth. (The radius of Earth is approximately 6400Km). Then suppose the wire is cut and its length is increased by 20 km. It is then placed back around the planet so that it is the same distance from Earth at every point. Could you walk under the wire?
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Treat the Earth as a sphere.
The perimeter would be the circumference of a circle with radius 6400 km.
C=2%2Api%2A6400
C%5B1%5D=40212km
Now if we add 20 km,
C%5B2%5D=40212%2B20
C%5B2%5D=40232km
Find the radius of the circle with that perimeter,
2%2Api%2AR=40232
R=6403 km
The difference in radii is
dR=6403-6400
dR=3km
You could easily fit yourself under that, in fact, on a cloudy day you wouldn't even see the wire.