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Kinetic Energy#

Definition: Kinetic Energy

The kinetic energy of a point mass \(m\) is defined as one-half of the product of \(m\) and its speed squared:

\[ \frac{1}{2}mv^2 \]

The (total) kinetic energy of a continuous mass distribution \(\rho\) with volume \(V\) is the integral

\[ \int_V \rho(\boldsymbol{r}) v(\boldsymbol{r})^2 \mathop{\mathrm{d}V}, \]

where \(v(\boldsymbol{r})\) is the velocity of the infinitesimally small point mass located at \(\boldsymbol{r}\).

The (total) kinetic energy of a physical system is the sum of the kinetic energies of its components.

Notation

\[ K \qquad E_{\text{k}} \qquad E_{\text{kin}} \]