B Quasistatic condition for a process involving a piston in a cylinder

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The discussion focuses on the quasistatic condition in processes involving a piston in a cylinder, defined by the relationship between the external change time scale (τ_exp) and the relaxation time (τ_relax). A quasistatic process occurs when τ_exp significantly exceeds τ_relax, allowing the system to remain near equilibrium. An example provided is the slow extraction of a piston from a thermally insulated gas-filled cylinder. The query arises on how to express the quasistatic condition using piston velocity (v) and relaxation time (τ_relax), leading to the proposed formula τ_exp = V(t)/(Av), where V(t) is the observed volume and A is the area. This formula indicates the time required to adjust the current volume based on the piston speed.
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The time scale on which the change (such as a change in external parameters or a external parameters or an addition of heat) takes place is referred to as τ_exp. The relaxation time τ_relax, on the other hand, is the time that the system needs to return to a state of equilibrium after a sudden change to return to a state of equilibrium. The condition quasistatic is fulfilled in the limiting case τ_exp/τ_relax → ∞

An example of a quasistatic process is the slow extraction of a piston from a thermally insulated cylinder filled with gas. How can I express this quasistatic condition with the piston velocity v and relaxation time τ_relax variables? In other words, my problem is if I only know the piston velocity v, how do I get τ_exp from this?
 
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By physical dimension analysis, how about
\tau_{exp}=\frac{V(t)}{Av} where V(t) is volume we are observing, A is area and v is speed of piston ? It’s time required to make up the current volume with the current piston speed.
 
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