MCQs on Fluctuating Stresses & Fatigue Failure
1 - Question
The stress represented by sin (t) + 1 belongs to which category?
a) Fluctuating Stresses
b) Alternating stresses
c) Repeated Stresses
d) Reversed Stresses
View Answer
2 - Question
The stress represented by sin (t) + 2 belongs to which category?
a) Fluctuating Stresses
b) None of the mentioned
c) Repeated Stresses
d) Reversed Stresses
View Answer
Answer:a
Explanation: The mean as well as the amplitude value is non zero hence it belongs to Fluctuation Stress Category.
3 - Question
The stress represented by sin (t) + 4 belongs to which category?
a) Alternating Stresses
b) None of the mentioned
c) Repeated Stresses
d) Reversed Stresses
View Answer
Answer: a
Explanation: The mean as well as the amplitude value is non zero hence it belongs to Alternation Stresses category which is the other name of Fluctuation Stresses.
4 - Question
The stress represented by cos (t) belongs to which category?
a) Fluctuating Stresses
b) Alternating Stresses
c) Repeated Stresses
d) Reversed Stresses
View Answer
Answer: d
Explanation: Half cycle is in tensile stress and other half in compressive stress, hence it belongs to Reversed Stresses Category.
5 - Question
If the mean stress value for a sinusoidal stress function is zero, then this type of stress falls in which category?
a) Fluctuating Stresses
b) Alternating Stresses
c) Repeated Stresses
d) Reversed Stresses
View Answer
SAnswer: d
Explanation: If mean is to be zero, then there must be compressive as well as tensile stresses and hence belongs to reversed stresses category.tresses
6 - Question
The phenomenon of decreased resistance of the materials to fluctuating stresses is the main characteristic of _____ failure.
a) Fracture
b) Fatigue
c) Yielding
d) None of the mentioned
View Answer
Answer: b
Explanation: Fatigue failure of the material is the failure at low stress levels under fluctuating syresses.
7 - Question
Fatigue failure is time dependent failure.
a) True
b) False
View Answer
Answer: a
Explanation: Fatigue failure is defined as time delayed fracture under cyclic loading
8 - Question
There is sufficient plastic deformation prior to fatigue failure, which gives a warning well in advance.
a) True
b) False
View Answer
Answer: b
Explanation: Fatigue cracks are not visible until they reach the surface and by that time the failure has already taken place. Material nevers enters in the plastic range.