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Contents Index Dark Mode Prev Up Next \(\newcommand{\vf}[1]{\mathbf{\boldsymbol{\vec{#1}}}}
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Section 8.5 Central Forces
In the introduction
Section 8.1 , we defined a central force as satisfying two characteristics. We can now write turn these descriptions of the characteristics into equations:
A central force depends only on the separation between the two bodies
\begin{equation}
\ff_{21} = -\ff_{12} = \ff(\rr_2-\rr_1)\tag{8.5.1}
\end{equation}
A central force points along the line connecting the two bodies
\begin{equation}
\ff_{21} = -\ff_{12} = \ff(\rr_2-\rr_1) = f(\rr) \,\rhat\tag{8.5.2}
\end{equation}
