If a spring load some energy and use it for opposing other forces, and a dash pot has a friction, physically the both shouldn't have the same force-displacement equation ?
In most of dash pots, we could find an inner spring right ?
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1\$\begingroup\$ Spring force is proportional to displacement; add a dashpot and you introduce a force proportional to velocity (derivative of displacement); add a mass and you introduce a force proportional to acceleration (derivative of velocity, and 2nd derivative of displacement). And these systems are, respectively, 0th order, 1st order and 2nd order. A similar relationship exists for resistor; inductor; capacitor. \$\endgroup\$ – Chu Jun 30 '18 at 7:39
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1\$\begingroup\$ ... derivative = multiply by s in Laplace TF. \$\endgroup\$ – Chu Jun 30 '18 at 8:16
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1\$\begingroup\$ I don't see how this is related to EE... \$\endgroup\$ – Sven B Jun 30 '18 at 15:29
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\$\begingroup\$ I'm voting to close this question as off-topic because this has nothing to do with EE \$\endgroup\$ – MCG Jul 11 '18 at 12:33
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A spring stores energy, a dashpot dissipates energy, so without going into any more detail than that, you know they must have different equations.
The spring delivers a force proportional to the displacement.
A dashpot delivers a force proportional to the velocity, or the rate of change of displacement. In most dashpots, you'll find a fluid being forced through a small orifice as the piston moves.
