Gas effusing through hole, working out time dependence

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SUMMARY

The discussion focuses on calculating the time dependence of gas density, n(t), and temperature, T(t), in a thermally insulated container with a small hole. The initial conditions include a gas density of n0 and temperature T0, with molecular mass m. The effusion rate is described by the equation N_L = (1/4) n A = (1/4) (N_0/v) A √(8kT/πm). To derive n(t) and T(t), the flux of energy must be analyzed using the open-system version of the first law of thermodynamics.

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Homework Statement
Consider instead a thermally insulated container of volume V with a
small hole of area A, containing a gas with molecular mass m. At time t = 0, the density is ##n_0## and temperature is ##T_0##. As gas effuses out through a small hole, both density and temperature inside the container will drop. Work out their time dependence, n(t) and T(t) in terms of the quantities given above.
Relevant Equations
##N_L = \frac{1}{4} n A <u> = \frac{1}{4} \frac{N_0}{v} A \sqrt{\frac{8kT}{\pi m}}##
Consider instead a thermally insulated container of volume V with a
small hole of area A, containing a gas with molecular mass m. At time t = 0, the density is ##n_0## and temperature is ##T_0##. As gas effuses out through a small hole, both density and temperature inside the container will drop. Work out their time dependence, n(t) and T(t) in terms of the quantities given above.

I know that ##N_L = \frac{1}{4} n A <u> = \frac{1}{4} \frac{N_0}{v} A \sqrt{\frac{8kT}{\pi m}}##, but not sure how to use this to find n(t) and T(t). I think I need to find the flux of the energy to know if the temperature is decreasing and then find n and t from that but not sure exactly how to do this. Any help greatly appreciated.
 
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This can be solved using the open-system (control volume) version of the 1st law. Are you familiar with that?
 

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