21
The stress necessary to initiate yielding is
Answer: considerably greater than that necessary to continue it
Questions
22
In a tensile test, near the elastic limit zone, the
Answer: tensile strain increases more quickly
23
If a material expands freely due to heating it will develop
Answer: no stress
24
The percentage reduction in area of a cast iron specimen during tensile test would be of the order of
Answer: negligible
25
The change in the unit volume of a material under tension with increase in its Poisson’s ratio will ,
Answer: decrease
26
The property of a material by virtue of which it can be beaten or rolled into plates is called
Answer: malleability
27
For which material the Poisson’s ratio is more than unity
Answer: none of the above
28
Poisson’s ratio is defined as the ratio of
Answer: lateral stress and longitudinal stress
29
The property of a material which allows it to be drawn into a smaller section is called
Answer: ductility
31
The materials which exhibit the same elastic properties in all directions are called
Answer: isotropic
32
The property of a material by virtue of which a body returns to its original, shape after removal of the load is called
Answer: elasticity
33
The total elongation produced in a bar of uniform section hanging vertically downwards due to its own weight is equal to that produced by a weight
Answer: half the weight of bar applied at lower end
34
The buckling load for a given material depends on
Answer: slenderness ratio, area of cross-section and modulus of elasticity
37
If a part is constrained to move and heated, it will develop
Answer: compressive stress
38
In a tensile test on mild steel specimen, the breaking stress as compared to ultimate tensile stress is
Answer: less
39
Which is the false statement about true stress-strain method
Answer: It does not exist
40
In the tensile test, the phenomenon of slow extension of the material, i. e. stress increasing with the time at a constant load is called
Answer: creeping
