Answer to Question #191913 in Mechanical Engineering for luke

Question

A three step shaft is connected as shown. Torque will be applied on the location provided. Considering each of the segments, 1,2, and 3, to have their own equivalent torsional spring constant, how are these torsional spring constants connected?

Answer 1

$\dfrac{∆\theta_2}{∆\theta_1} = \dfrac{∆\theta_3}{∆\theta_2}$

given that the segments are connected to each other with variable lengths