According to ASME code, maximum allowable shear stress is taken as X% of yield strength or Y% of ultimate strength.
(a) X=30 Y=18
(b) X=30 Y=30
(c) X=18 Y=18
(d) X=18 Y=30
I was asked this question by my mentor.
This question is from the Shaft Design in chapter Shafts, Keys and Couplings of Machine Design