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- $C = 2πr.$

- $ΔC ≈ \frac{dC}{dr} Δr$

- $=2π Δr $

- $=2π(1)$ meter

- $ ≈ \color{blue} {6.28} m$

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