Question

For a gearing system, the equivalent system is made consisting of three rotors. How many nodes will this new equivalent system will have?

(a) 0

(b) 1

(c) 2

(d) 3

The question was posed to me in an interview for job.

My question comes from Free Torsional Vibrations of a Geared System in division Torsional Vibrations of Machine Dynamics

Answer 1

Correct answer is (c) 2

To explain: When a gearing system is converted into an equivalent system consisting of three rotors, it will have two nodes on the shaft as the three-rotor system produces two nodes.