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Equation 139 · Part 1 · The Bend an Elevator Cannot Fake

Symbol phi_,zz

ϕ,zz h2=2 σy\phi_{,zz}\,h^2 = \sqrt2\,\sigma_y
ϕ,zz\phi_{,zz}

What this part means

phi_,zz is part of the quantity the equation computes from the expression on the right.

Its job in the formula

phi_,zz is part of the quantity the equation computes from the expression on the right.

The passage around this formula

​ σ y ​ . Setting signal equal to noise, ϕ,zz\phi_{,zz}\,h2h^2 = 2\sqrt2\,σy\sigma_y , gives

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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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