Thus, the total average impulse contributed by a molecule with an $x$-component velocity ranging between $v_x$ and $v_x+\mathrm dv_x$, is given by $$2mv_x\cdot\frac{v_x\tau}{L_x}\cdot\sqrt{\frac{\alpha}{\pi}}e^{-\alpha v_x^2}\mathrm dv_x$$

where $v_x$ is velocity of particle, $τ$ is the time during which the collision occurs with the wall of container and $L_x$ is the length of wall of the container.

What effect does factor $v_xτ/L_x$ explain in the equation?

  • Consult any standard text on Kinetic Theory of Gases. I'll recommend Loeb. – sbp Oct 12 at 9:59
  • The formula looks totally wrong. And wtf is $L_x$? – Kostas Oct 12 at 11:16
  • Actually, gas is assumed to be in container of dimensions $L_x$, $L_y$, and $L_z$. – Nasir Aziz Oct 13 at 7:00

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