This problem requires you to solve for the torque based on the torsional shear stress formula before you can solve for the angle of twist. If you want to skip the calculation of J, hang on until the end of the video (or click here    • Torsion  Combined Torque Twist Problem  .


See also

Torsion Torque & shear stress
   • Torsion  Torque formula and force co...  


Torsion Angle of Twist with a Twist
   • Torsion  Angle of twist and solving ...