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3.08×10−6s−2
Why this formula appears here
For Earth modelled as a point mass, Φ(r) = -GM/r gives a radial second derivative of magnitude 2GM/R3 and, since Φ is harmonic in vacuum, transverse second derivatives of magnitude GM/R3 with the opposite sign — a trace-free tensor in the exact ratio 2:{-1}:{-1} . With the standard gravitational parameter GM⊕ = 3.986×10^{14}\,m3s−2 and mean radius R⊕ = 6.371×10^{6}\,m , this gives GM⊕/R⊕3 ≈ 1.541×10^{-6}\,s−2 and a radial magnitude of 3.08×10^{-6}\,s−2 , matching the standard geodetic free-air gravity gradient of about 3.086×10^{-6}\,s−2 , or 0.3086 milligal per metre,…
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Equation 132 · Evolutionary Physics
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For Earth modelled as a point mass, Φ(r) = -GM/r gives a radial second derivative of magnitude 2GM/R3 and, since Φ is harmonic in vacuum, transverse second derivatives of magnitude GM/R3 with the opposite sign — a trace-free tensor in the exact ratio 2:{-1}:{-1} . With the standard gravitational parameter GM⊕ = 3.986×10^{14}\,m3s−2 and mean radius R⊕ = 6.371×10^{6}\,m , this gives GM⊕/R⊕3 ≈ 1.541×10^{-6}\,s−2 and a radial magnitude of 3.08×10^{-6}\,s−2 , matching the standard geodetic free-air gravity gradient of about 3.086×10^{-6}\,s−2 , or 0.3086 milligal per metre,…
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