% Uwe Ziegenhagen
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\begin{eqnarray*}
\frac{\Delta U}{\Delta h} &=& \frac{24 \volt}{1 \micro\meter} \\
\Delta U &=& \frac{24 \volt \cdot 0.35 \micro\meter}{1 \micro\meter} \\
\Delta U &=& 8.4 \volt
\end{eqnarray*}

\[\frac{0.25 \centi\meter \cdot 4.35 \nano\meter}{7.6 \centi\meter}= 0.143 \nano\meter => 1.43 \cdot 10^{-10} \meter\]

\[10^{-11} \meter \cdot \sqrt{10^{-18} \joule} \leq 1.05 \cdot 10^{-34} \joule\second \cdot \sqrt{\frac{2}{9.11\cdot 10^{-31} \kilogram}} \]

\end{document}
