Question 1:Endurance limit of a beam subjected to pure bending decreases with [2019 , Set 2]
Question 2:A cylindrical shaft is subjected to an alternating stress of 100 MPa. Fatigue strength to sustain 1000 cycles is 490 MPa. If the corrected endurance strength is 70 MPa, estimated shaft life will be [2006]
Explanation

By concept of straight line,

At y = 2
⇒ x = 5.4501
log10N = 5.4501, N = 281914
Question 3:The S-N curve for steel becomes asymptotic nearly at [2004]
Question 4:In terms of theoretical stress concentration factor kt and fatigue stress concentration factor kt, the notch sensitivity q is expressed as [2004]
Question 5:Which one of the following is the most conservation fatigue failure criterion? [2015, Set-1]
Question 6:A static load is mounted at the centre of a shaft rotating at uniform angular velocity. This shaft will be designed for [2002]
Explanation
Shaft will be designed for fatigue loading.
Question 7:The yield strength of a steel shaft is twice its endurance limit. Which of the following torque fluctuations represent the most critical situation according to Soderberg criterion? [1993]
Explanation

τa is highest in (a)
Question 8:The process of shot peening increases the fatigue life of steel springs mainly because it results in [1990]
Explanation
Shot preening increases fatigue life of springs
Question 9:Stress concentration in a machine component of a ductile material is not so harmful as it is in a brittle material because [1989]
Explanation
Local yielding reduces stress concentration effect.
Question 10:A ductile material having an endurance limit of 196 N/mm2 and the yield point at 294 N/mm2 is stressed under variable load. The maximum and minimum stresses are 147 N/mm2 and 49 N/mm2. The fatigue stress concentration factor is 1.32. The available factor of safety for this loading is [1987]
Explanation
Consider Soderberg equation


FOS = 1.5