Question:-
A cold roller steel shaft is designed on the basis of maximum shear stress theory. The principal stresses induced at its critical section are 60 MPa and -60 MPa respectively. If the yield stress for the shaft material is 360 MPa, the factor of safety of the design is
Option (A)
2
Option (B)
3
Option(C)
4
Option(D)
6
Correct Option:
(B)
Question Solution:
tmax = {(s1-s2) / 2} = {(60-(-60)) / 2} = 60MPA
According to maximum shear stress theory Yield stress in shear = Sse = 0.5 x Syt = 0.5 x 360 = 180
\ tallowable = (Sse/Fos)
\ Fos = (Sse / tallowable)
= 180/60 = 3
question-answer-faq-9316