Find the fraction of molecules whose velocity projections on the `x` axis fall within the inerval from `v_x` to `v_x + dv_x`, while the moduli of perpendicular velocity components fall within the inerval from `v_( _|_)` to `v_(_|_) + dv_(_|_)`. The mass of each molecule is `m`, and the temperature is `T`.

Explanation

`d^3 v = 2 pi v_(_|_) dv_(_|_) dx_x`
Thus `d n(v) = N((m)/(2 pi kT))^(3//2) e-(m)/(2 kT) (v_x^2 + v_(_|_)^2) dv_x 2 pi v_(_|_) dv _(_|_)`.