The translation table finishes here. Mass $m$ becomes moment of inertia $I$; speed $v$ becomes angular velocity $\omega$; and the two great bookkeeping quantities of mechanics come across unchanged in shape. Kinetic energy $\tfrac{1}{2}mv^{2}$ becomes $KE_{rot} = \tfrac{1}{2} I \omega^{2}$ — KE equals one-half I omega squared — where $I$ is in $\mathrm{kg \cdot m^2}$, $\omega$ is in $\mathrm{rad/s}$, and the answer is in joules, the same joules as everywhere else.

Momentum $p = mv$ becomes angular momentum $L = I\omega$ — L equals I omega — in $\mathrm{kg \cdot m^2/s}$. No ½, no square: momentum never had either, and its rotational twin does not acquire them. Telling the two apart on an exam paper is a units question and nothing more. Joules means energy; $\mathrm{kg \cdot m^2/s}$ means momentum.

The square in the energy is where flywheels earn their keep: double the speed and a wheel banks four times the energy, while its angular momentum merely doubles. That is why a modest steel disk spun fast can smooth a punch press through a stroke that would otherwise stall the motor — and why the same disk is a serious object to be standing beside when a bearing lets go.