Experimental Verification of the Behaviour of the Different Expressions for Measuring Amplitude Dependent Damping

The agreement between the intrinsic damping, obtained from the sustained oscillations measurements, and the values measured directly in forced oscillations has been verified. Therefore, it is possible to measure directly the intrinsic damping from forced oscillations, without additional calculations and with minor effort. At the same time the damping behaviour measured by different modes with a torsion pendulum, i. e. forced oscillations, sustained oscillations and free decay, in presence of amplitude dependent damping was also studied and similar results are obtained..