A rigid T-shaped structure lies at rest on a horizontal, frictionless surface. The structure is constructed from two uniform rods: a handle of mass \(M\) and length \(L\), and a crossbar of mass \(m\) and total length \(2D\). The handle is attached at one end to the exact center of the crossbar. The structure is pinned to the surface at the junction of the two rods by a frictionless vertical axis, allowing it to rotate freely in the horizontal plane.

The rotational inertia of a uniform rod of mass \(m_0\) and length \(\ell\) is \(\dfrac{1}{12}m_0\ell^2\) about its center and \(\dfrac{1}{3}m_0\ell^2\) about its end.