changes.mady.by.user Arthur Aslanyan (Nafta College)
Saved on Sep 11, 2022
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\frac{\partial \rho}{\partial t} + \nabla (\rho \, {\bf u}) = \sum_k \rho(t, {\bf r}) \,cdot \dot q_k(t) \cdot \delta({\bf r}-{\bf r}_k)
