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Equation 123 · Part 3 · The Bend an Elevator Cannot Fake

Symbol phi_,zz

y2−y1=ϕ,zz h2+O(h4).y_2 - y_1 = \phi_{,zz}\,h^2 + O(h^4).
ϕ,zz\phi_{,zz}

What this part means

phi_,zz is one of the signed contributions combined to compute the quantity on the left.

Its job in the formula

phi_,zz is one of the signed contributions combined to compute the quantity on the left.

The passage around this formula

…radial magnitude of 3.08×\times10^{-6}\,s−2\mathrm{s^{-2}} , matching the standard geodetic free-air gravity gradient of about 3.086×\times10^{-6}\,s−2\mathrm{s^{-2}} , or 0.3086 milligal per metre, to three figures [ 15 ] . So ϕ,zz\phi_{,zz} ≈\approx 3.08×\times10^{-6}/c2c^2 ≈\approx 3.43×\times10^{-23}\,m−2\mathrm{m^{-2}} .

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Learn the underlying idea

A subscript is a label attached below a symbol. It often selects a time step, component, category, or member of a sequence.

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Sources cited in the surrounding passage

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