In dictionaries:
second moment of area
(engineering) A measure of a body's resistance to bending.
second moment of inertia
(engineering) A measure of a body's resistance to bending; second moment of area.
Second polar moment of area
The second polar moment of area, also known (incorrectly, colloquially) as "polar moment of inertia" or even "moment of inertia", is a quantity used to describe resistance to torsional deformation (deflection), in objects (or segments of an object) with an invariant cross-section and no significant warping or out-of-plane deformation.
Second moment method
In mathematics, the second moment method is a technique used in probability theory and analysis to show that a random variable has positive probability of being positive.
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