Diagram shows an aluminum shaft A B with a support at A, marked 1 of length 2,000 millimeters and a brass shaft B C with a support at C, marked 2 of length 800 millimeters with a flange in between at B. The shafts are centered on the x axis. A torque T is applied at B.

For stainless steel shaft (1):

L1=2,000 mm
G1=86 GPa=86,000 N/mm2
J1=2,207,951 mm4

Rearrange the torque-twist relationship for shaft (1) to solve for T1:

T1=ϕ1J1G1L1
=(3˚)(π rad180˚)×(2,207,951 mm4)(86,000 N/mm2)2,000 mm
=4,971,146 N-m =4.97 kN-m