Finding The Maximum Shearing Stress From Multiple Torques in Cylindrical Rod

How to find what section of a cylindrical shaft that changes diameter between applied torques has the maximum shearing stress. Using the max shear stress equation you can evaluate each section of the shaft individually to determine the max sharing stress that will be seen in that individual section dependent upon the amount of torque that the shaft sees in that particular section.
Mechanics of Materials solution to Problem 3.11 from the textbook;
Knowing that each portion of the shafts AB, BC, and CD consist of a solid cylindrical rod, determine (a) the shaft in which the maximum shearing stress occurs, (b) the magnitude of that stress.
Torque is a bit of a twisty subject! Change my mind!
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[@mihiranganipun9023]

Thank you so much Mr. Daniel.

[@GameVOVE]

thanks a lot

[@affanahmedkhan7362]

love from PAKISTAN

[@GameVOVE]

you can use Mpa instead of Pa. By this way, your results may seen more properly

[@ziqmoon8800]

is CD equal to DC

[@rushwalker780]

Sir what about portion b

[@rushwalker780]

Is CD is the magnitude

[@holguinchristianiln.3563]

Sir what about minimum shearing stress in shaft AB

[@eamongriffiths8533]

The minimum is zero at the center or the shaft. I believe because c would be equal to 0 and thus tow would aswell