As incredible as it may seem, the cable would only have to be about 6.3 meters (not km!) longer in order to be raised one meter all the way around the planet. Here's why.

The circumference of $a$ disc with radius $r$ is given by

If $r$ is changed by $Δr,$ then the corresponding change in circumference is given by Note that this is independent of the radius of the planet! Thus, the same answer holds for Jupiter (or any spherical object).


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