#StartUvod
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\vskip-2.9mm\noindent
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\begin{tabular}{lr}
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\begin{minipage}[t]{0.5\textwidth}
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Na vi"sini $h=/*/h/*/\mathrm{m}$ nad nevtralno prevodno podlago
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se nahajata prema vodnika polmera $r_0=/*/r0/*/$m.
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Razdalja med njima je $d=/*/d/*/$m, naelektrena sta z
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$\pm{q}=\pm/*/q/*/$C/m naboja na dol"zinsko enoto.
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To"cki A in B sta na meji med ravno podlago in zrakom.
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\end{minipage}
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\hskip0.01\textwidth
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\begin{minipage}[t]{0.4\textwidth}
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\vskip-5mm
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\begin{tikzpicture}[scale=0.7]
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\fill[color=black] (0,2) circle (0.2);
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\fill[color=black] (4,2) circle (0.2);
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\node[above] at (0.4,2) {$-q$};
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\node[above] at (4.4,2) {$+q$};
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\draw [dashed,stealth-stealth] (-1,0) -- (-1,2);
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\draw [dashed,stealth-stealth] (0,0.5) -- (4,0.5);
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\draw [dotted] (0,0) -- (0,3);
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\draw [dotted] (-1.5,2) -- (5.5,2);
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\draw [dotted] (4,0) -- (4,3);
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\fill[color=black!20] (-3.0,0) -- (8.5,0) -- (8.5,-0.8) -- (-3.0,-0.8);
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\node[left] at (-1,1) {$h=/*/h/*/$m};
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\node[above] at (2,0.5) {$d=/*/d/*/$m};
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\node[below] at (4,0) {A};
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\node[below] at (8,0) {B};
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\fill[color=black] (4,0) circle (0.05);
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\fill[color=black] (8,0) circle (0.05);
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\draw [dashed,stealth-stealth] (4,0.5) -- (8,0.5);
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\node[above] at (6,0.5) {$d=/*/d/*/$m};
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\end{tikzpicture}
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\end{minipage}
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\end{tabular}
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\vskip-2mm
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#EndUvod
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#StartPodnaloga
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Kolik"sna je absolutna vrednost elektri"cne poljske jakosti
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v to"cki A?
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#EndPodnaloga
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#StartRezultat
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TeX: E(\mathrm{A})
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izpis: prefix 3
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enota: V/m
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formula: eps0=8.854e-12;EA=q/(pi*eps0*h)*abs(-1+1/(1+(d/h)^2));EA
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napacna: q/(2*pi*eps0*h)*abs(-1+1/(1+(d/h)^2))
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napacna: 5.29864*EA
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napacna: q/(pi*eps0*h)*abs(1/(1+(d/h)^2))
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#EndRezultat
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#StartPodnaloga
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Kolik"sno je razmerje povr"sinskih gostot naboja v to"ckah A in B?
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#EndPodnaloga
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#StartRezultat
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TeX: \sigma_\mathrm{A}/\sigma_\mathrm{B}
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izpis: dec 3
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enota:
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formula: ka=d/h;(1+4*ka^2)/3
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napacna: (1+ka^2)/3
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napacna: (1+4*ka^2)
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napacna: (1+2*ka^2)/3
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#EndRezultat
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#StartPodnaloga
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Kolik"sna je kapacitivnost dvovoda na enoto dol"zine?
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#EndPodnaloga
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#StartRezultat
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TeX: c
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izpis: sci 3
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enota: F/m
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formula: D=sqrt(d^2+4*h^2);c=pi*eps0/log(2*h*d/(r0*D));c
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napacna: 2.4869128*c
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napacna: 0.84128*c
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napacna: 0.6838*c
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napacna: 1.376*c
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napacna: 19.14869128*c
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#EndRezultat
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|
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#StartSkalar
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ime: q
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izpis: sci 2
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nacin: FixedVals 40e-9 50e-9 60e-9
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#EndSkalar
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#StartSkalar
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ime: d
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izpis: sci 1
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nacin: FixedVals 6 8
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#EndSkalar
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#StartSkalar
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ime: h
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izpis: sci 1
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nacin: FixedVals 1 2
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#EndSkalar
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#StartSkalar
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ime: r0
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izpis: sci 1
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nacin: FixedVals 5e-3 6e-3 8e-3
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#EndSkalar
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