Question

For a vibration system having different shaft parameters, calculate which of the following cannot be the diameter of the equivalent shaft if the diameters of shafts in m are: 0.05, 0.06, 0.07.

(a) 0.05

(b) 0.06

(c) 0.07

(d) 0.08

The question was posed to me in unit test.

Asked question is from Torsionally Equivalent Shaft in section Torsional Vibrations of Machine Dynamics

Answer 1

The correct answer is (d) 0.08

To explain I would say: In a torsionally equivalent shaft, it is assumed that the equivalent shaft has the diameter which is equal to one of the diameters of the shaft and equivalent length is calculated.