(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The particles of an ink blob dropped into a large container of water diffuse outward and obey the radial diffusion equation:

dn/dt = (D/r^{2}) (d/dr) (r_{2}* (dn/dr) )

where n(r,t) is the density of ink particles at point r at time t and D is the diffusion constant.

Verify, by direct differentiation that:

n_{s}= N*(1 / (4*pi*D*t) )^{3/2}* e^{r2/4Dt}

is a solution of this equation and satisfies the condition that the total number of ink particles is N for any value of t.

2. Relevant equations

3. The attempt at a solution

I have no idea?

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# Homework Help: Ink diffusing in water - partial diff equations

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