Date: Jun 17, 2011 5:06 AM
Author: Nasser Abbasi
Subject: Re: capacitor equation solution not working

On 6/16/2011 9:09 PM, J and B wrote:
> I am trying to solve a very simple circuit, one that has only a capacitor in
> it. What am I doing wrong? The final graph should show that the capacitor
> has discharged, but its staying constant. I have current starting at t=10
> and ending at t=60.
> I hope I have used the correct way to put in my code, I am using a new
> computer and I having trouble with my email program. Any advice would be
> appreciated.
>
> Thanks
>
> My code.
> I[t_]:= If[t<10||t>60,0,1]
> Plot[i[t],{t,0,100}]
> Eq=v'[t]==i[t]/c
> c=1;
> Soleq==v[t]/.NDSolve[{eq,v[0]==0},v[t],{t,0,100}],[[1]]
> Plot[soleq,{t,0,100}]


Mathematica is case senstive. Try this:

----------------
f[t_] := If[t < 10 || t > 60, 0, 1]
Plot[f[t], {t, 0, 100}]
eq = v'[t] == f[t]/c
c = 1;
soleq = v[t] /. First[NDSolve[{eq, v[0] == 0}, v, {t, 0, 100}]]
Plot[soleq, {t, 0, 100}]
----------------

--Nasser