A hot short metal is_________________?
(A) brittle when cold
(B) brittle when hot
(C) brittle under all conditions
(D) ductile at high temperature
(D) hard when hot
Rankine’s theory of failure is applicable for following type of materials___________________?
(A) brittle
(B) ductile
(C) elastic
(D) plastic
(D) tough
Tensile strength of a mild steel specimen can be roughly predicted from following hardness test_________________?
(A) Brinell
(B) Rockwell
(C) Vicker
(D) Shore’s sceleroscope
(D) none of the above
In the case of an elastic bar fixed at upper end and loaded by a falling weight at lower end, the shock load produced can be decreased by_________________?
(A) decreasing the cross-section area of’ bar
(B) increasing the cross-section area of bar
(C) remain unaffected with cross-section area
(D) would depend upon other factors
(D) none of the above
If a load W is applied instantaneously on a bar; then the stress induced in bar will___________________?
(A) be independent of ratio of mass of load W to mass of bar (y)
(B) increase with increase in y
(C) decrease with decrease in y
(D) depend on other considerations
(D) none of the above
Stress concentration is caused due to_____________________?
(A) variation in properties of material from point to point in a member
(B) pitting at’points or areas at which loads on a member are applied
(C) abrupt change of section
(D) all of the above
(D) none of the above
Plastic flow in ductile materials_____________________?
(A) increases the seriousness of static load-ing stress concentration
(B) lessens the seriousness of static load¬ing stress concentration
(C) has no effect on it
(D) depends on other considerations
(D) none of the above
The fatigue life of a part can be improved by_____________________?
(A) electroplating
(B) polishing
(C) coating
(D) shot peening
(D) heat treating
For steel, the ultimate strength in shear as compared to ultimate strength in tension is ___________________?
(A) same
(B) 1/2
(C) 1/3
(D) 1/4
(D) 2/3
Resistance to fatigue of a material is measured by________________?
(A) Young’s modulus
(B) coefficient of elasticity
(C) elastic limit
(D) ultimate tensile strength
(D) endurance limit