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

Suppose an initial number density of ink particles (i.e. number per unit length) is

given by:

[tex]f(x) = 2Nx[/tex] ; for [tex]0 < x < 1[/tex]

[tex]f(x) = 0[/tex] ; otherwise.

Suppose also add a point source containing [itex]N[/itex] molecules at the point [itex]x = − 1[/itex].

(a) Showing that the initial total number of molecules at [itex]x > 0[/itex] is equal to the initial total number of molecules at [itex]x < 0[/itex].

(b) Using the standard time-dependent solution of the 1-D diffusion equation with initial conditions to find an expression

for the number density of molecules as a function of [itex]t[/itex] at the point [itex]x = 0[/itex].

2. Relevant equations

Within the problem statement and solutions.

3. The attempt at a solution

I have no idea how to even go about where to start

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# Homework Help: Initial Number Density of Ink Particles

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