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Would electrical reactance and physical inertia be appropriate general analogies? Each is a resistance to change. I've thought of trying to construct a table of similarities between disciplines to speed and clarify understandings as courses seemed to converge on these evaluations.

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    \$\begingroup\$ These are quite common analogies. Inductance is like a flywheel, capacitance is like a spring. Both are forms of energy storage. BTW, when I was an undergrad, I rather amusingly discovered from mech eng friends that their lecturers used electrical analogies to explain second order mechanical systems. I guess it is just a way of broadening perspective. \$\endgroup\$ – Jon Mar 7 '18 at 9:53
  • \$\begingroup\$ This is what I'm talking about. I found an explanation of electrical reactance as a generalized term for both capacitors and inductors and I know mass' inertia is the resistance to change in motion. I was additionally e.g. trying to correctly relate a concept of "thermal inertia" (heat capacity) to mass inertia; heat conductance with electrical resistance; mass as "energy condensate". I thought there might be better uniform correlations than current engineering typically gives effort toward. I find some of those examples not clear, overlapping and inconsistent (no personal offense meant). \$\endgroup\$ – LouF Mar 7 '18 at 10:22
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I've thought of trying to construct a table of similarities between disciplines

Why bother when there are plenty on the web: -

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There are literally loads of them if you search "electrical and mechanical equivalent table".

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  • \$\begingroup\$ Thanks, but I just don't find those at all parallel. Force and current the same? No. At least force and voltage. If they are, then I am not recognizing the concepts correctly. \$\endgroup\$ – LouF Mar 7 '18 at 10:31
  • \$\begingroup\$ @LouF they are interchangeable. Pressure can be regarded as voltage and if that pressure causes movement then movement can be regarded as current. In a magnetic circuit, current (amps x turns) can be regarded as equivalent to voltage (huh I hear you say). I tend to regard a flywheel like a capacitor but in different analysis scenarios it can be regarded as a spring. \$\endgroup\$ – Andy aka Mar 7 '18 at 10:45
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Would electrical reactance and physical inertia be appropriate general analogies?

Yes, a mass-spring system has exactly the same energy, impedance, displacement, force equations as an LC system has energy, impedance, charge and voltage equations.

Constructing a table of all the equivalent variables is a good way to learn and explore.

There are plenty of examples on the web to cross-check your work as you progress.

Take care to match pressure-like things as voltage and pressure, displacement-like things like distance and charge, and speed-like things like current and speed, to get the best correspondence between mechanical and electrical.

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