What is torsion rigibility and supports with examples?

Torsional rigidity, or torsional stiffness, refers to a material's ability to resist twisting or torsional deformation when subjected to a torque. It is defined as the torque required to produce a unit angle of twist in a structural element. For example, a solid steel rod has high torsional rigidity, making it suitable for applications like drive shafts in vehicles, where it must withstand significant twisting forces without deforming. In contrast, a rubber rod has low torsional rigidity, making it inappropriate for such applications but suitable for dampening vibrations.