[[Torque and Rotational Dynamics]]
For a point mass:$$I=mr^2$$
$I$ is rotational inertia (kg * $m^2$)
m is mass
r is radial distance

Several discrete objects:
$$I_{tot}=\Sigma I_i=\Sigma m_i r^2$$

# Parallel Axis Theorem
Essentially shifting the axis and calculating the new inertia.
$$I'=I_{cm}+Md^2$$
- $I$' is rotational inertia about the parallel axis (kg⋅m²)
- $I_{cm}$ is rotational inertia about the center-of-mass axis (kg⋅m²)
- $M$ is the total mass of the system (kg)
- $d$ is the perpendicular distance between the two parallel axes (m)