Torsional Rigidity is defined as how much an object of specified material resists twisting force, also known as torque. It is based on both the material of the object, as well as its shape. And is denoted by TJ. Torsional Rigidity is usually measured using the Kilonewton Square Meter for Torsional Rigidity. Note that the value of Torsional Rigidity is always negative.