i*******n
发帖数: 166 | 1
这个一点儿也不难呀
不就是v_x*f(v_x)从零到正无穷积分吗 其中f(v_x)是Maxwell分布(Gaussian)
这个积分很easy就出来了 注意要除以1/2(PARTICLES MOVING IN THE +X DIRECTION
难道我理解错了么? | c*****t
发帖数: 1879 | 2 temperature is the average kinetic energe of the particles.
T = 1/2 m v^2
v = sqrt (2T/m)
Since the probability of a particle moving toward any direction
is the same, regardless its speed, the average speed of the
particle moving toward +X direction is
v = sqrt (2T/m) | a**u
发帖数: 99 | 3 distribution function: f(px,py,pz)=const×exp[-p^2/2mkT].
Here p is a vector p=(px,py,pz) & p^2=px^2+py^2+pz^2.
average of vx pf those move in the +X direction is:
Integrate[f(px,0,0)×px/m,{px,0,∞}]。 |
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