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\Large\centerline{\bf Central Forces}
\normalsize\centerline{\bf Finding an Electron Inside the Bohr Radius}
\bigskip


For an electron in the $1s$ state of hydrogen,

\begin{equation*}
\psi_{100}\left(r,\theta,\phi\right)=\dfrac{1}{\sqrt{a_0^3 \pi}}e^{-r/a_0},
\end{equation*}

\begin{enumerate}
\item Calculate the probability that this electron would be found within one Bohr radius of the center $\left(P_{r<a_0}\right)$.
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\item What is one thing you have learned from this activity that you want to remember?
\end{enumerate}

\vfill
\leftline{\it by David McIntyre and Mary Bridget Kustusch}
\leftline{\copyright 2012 David McIntyre}
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