On 26th April, 2018

Rigidity Modulus of a wire – Torsional Pendulum

Dr. K. Vagdevi ,Department of Physics

This is an experiment to find rigidity modulus of a suspended wire using torsional pendulum. This is done using torsion pendulum, vernier calipers, screw gauge, circular disc and a stop watch. Torsion is the twisting of an object due to applied torque. A torsion pendulum is an oscillator for which the restoring force is torsion. Rigidity modulus or shear modulus is the ratio of shear stress to the displacement per unit sample length. When a circular disc is suspended through a wire, it undergoes torsion or coupling effect. This effect is used to determine the rigidity modulus of the suspended wire. The experiment is done through Virtual Lab and the values are compared by real time performance using various types of wires.


L. Rohith (17241A04L2), ECE
K. Jyothirmai (17241A04K1),ECE
N. Venkata Naga Sai (17241A04M3),ECE


Torsion springs are used in torsional pendulum clocks. In such clocks a torsion spring is used to suspend a wheel shaped weight from the centre of the clock.