The kinetic energy of a particle is $\mathrm{K}=12 \mathrm{mv} 2, \quad K=\frac{1}{2} m v^{2}$, where $m$ is the mass of the particle and $v$ is its speed. Show that 1 joule (J), the SI unit of energy, is equivalent to $1 \mathrm{~kg} \cdot \mathrm{m}^{2} / \mathrm{s}^{2}$.