Editing TheOtherRopeAroundTheEarthSolution
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For the problem statement: * The Other Rope Around the Earth ---- The rope stretches from the top of the pole to the horizon. Suppose the angle subtended by the rope is t, the radius of the Earth is R, and the distance to the horizon is D. Then * (1) D^2+R^2 = (R+h)^2 * (2) D = R.tan(t) * (3) R.t + 3 = D. Solving is tough, but we use: * (4) tan(t) ~~ t + t^3/3 and so: * (5) R.t + 3 = R.tan(t) [ from (2) and (3) ] * (6) t + 3/R ~~ t + t^3/3 [ from (5) and (4) ] * (7) t^3 ~~ 9/R [ rearranging (6) ] Thus t ~~ 0.0112233... and we get: (drum roll please ...) h ~~ 401 metres. ---- See: * The Other Rope Around the Earth * Big List of Topics