Sources and sinks

<p>In the <a href="/facts/Physical_sciences/30ztjEKK">physical sciences</a>, <a href="/facts/Engineering/RFVg8H3I">engineering</a> and <a href="/facts/Mathematics/pxTouaz4">mathematics</a>, sources and sinks is an analogy used to describe properties of <a href="/facts/Vector_field/ccFNuPPp">vector fields</a>. It generalizes the idea of fluid sources and sinks (like the <a href="/facts/Tap_(valve)/HT7EnzzN">faucet</a> and <a href="/facts/Drain_(plumbing)/tnLavsTX">drain</a> of a bathtub) across different scientific disciplines. These terms describe points, regions, or entities where a vector field originates or terminates. This analogy is usually invoked when discussing the <a href="/facts/Continuity_equation/GVav2Vet">continuity equation</a>, the <a href="/facts/Divergence/zpwwkFoU">divergence</a> of the field and the <a href="/facts/Divergence_theorem/pUGKF1N2">divergence theorem</a>. The analogy sometimes includes swirls  and saddles for points that are neither of the two.
</p><p>In the case of <a href="/facts/Electric_field/tt4MooBs">electric fields</a> the idea of flow is replaced by <a href="/facts/Field_line/Nxr20d47">field lines</a> and the sources and sinks are <a href="/facts/Electric_charge/xxsBfmlB">electric charges</a>.
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Sources and sinks open-in-new

Sources and sinks