Description : Factor of safety for fatigue loading is the ratio of (a) elastic limit to the working stress (b) Young's modulus to the ultimate tensile strength (c) endurance limit to the working stress (d) elastic limit to the yield point
Last Answer : (c) endurance limit to the working stress
Description : Failure of a material is called fatigue when it fails (a) at the elastic limit (b) below the elastic limit (c) at the yield point (d) below the yield point
Last Answer : (d) below the yield point
Description : When a material is subjected to fatigue loading, the ratio of the endurance limit to the ultimate tensile strength is (a) 0.20 (b) 0.35 (c) 0.50 (d) 0.65
Last Answer : (c) 0.50
Description : The relationship between the alternating stress and mean stress is given by the following equation: σ a =σ e [1-(σ m /σ u )x], where σ e is the fatigue limit for completely reversed loading. The value of x for Gerber line is equal to _________ a) 1 b) 2 c) 0.5 d) -1
Last Answer : b) 2
Description : The ability of materials to develop a characteristic behavior under repeated loading known as ___________ a) Toughness b) Resilience c) Hardness d) Fatigue
Last Answer : d) Fatigue
Description : The connecting rod bolts are tightened up with the initial tension greater than external load so that (A) Failure of bolt will be static (B) The resultant load on bolt will not be affected by ... ) The bolt will not fail by fatigue although the external load is fluctuating (D) All the three
Last Answer : (D) All the three
Description : The endurance or fatigue limit is defined as the maximum value of the stress which a polished standard specimen can withstand without failure, for infinite number of cycles, when subjected to (a) static load (b) dynamic load (c) static as well as dynamic load (d) completely reversed load
Last Answer : (d) completely reversed load
Description : Among maximum shear stress theory and distortion energy theory, which gives the higher value shear yield strength? a) Maximum shear stress theory b) Distortion energy theory c) Both give equal values d) Vary from material to material
Last Answer : b) Distortion energy theory
Description : In cold working of metal as compared to its hot working (A) Cracks and blow holes are eliminated (B) Ductility and impact strength improves (C) Appreciable strain hardening is produced (D) Yield stress, hardness and fatigue strength is not at all affected
Last Answer : (C) Appreciable strain hardening is produced
Description : Paraffin base crude oil as compared to asphalt base crude gives (A) Higher yield of straight run gasoline (B) Higher octane number gasoline (C) Lower viscosity index lube oil (D) Poorer yield of lube oil
Last Answer : (A) Higher yield of straight run gasoline
Description : Catalytic cracking compared to thermal cracking of residue of vacuum distillation of crude oil (A) Gives higher yield of petrol (B) Lower octane number of petrol (C) Higher sulphur content in the product (D) Higher gum forming material in petro
Last Answer : (A) Gives higher yield of petrol
Description : Cylindrical roller bearing has a lower load capacity as compared to deep groove ball bearing. (a) True (b) False
Last Answer : (b) False
Description : Cylindrical load bearing has lower load capacity as compared to deep groove ball bearing. a) True b) False
Last Answer : b) False
Description : The connecting rod bolts are tightened up so that the initial tightening stress (A) Approaches yield point (B) Approaches endurance limit (C) Approaches (yield point stress/factor of safety) (D) Approaches (endurance limit stress/factor of safety)
Last Answer : (A) Approaches yield point
Description : Manganese is added in low carbon steel to A. Make the steel tougher and harder B. Raise the yield point C. Make the steel ductile and of good bending qualities D. All of the above
Last Answer : C. Make the steel ductile and of good bending qualities
Description : _____ is a surface fatigue failure which occurs when the load on the bearing part exceeds the surface endurance strength of the material. (a) Scoring (b) Pitting (c) Corrosion
Last Answer : (b) Pitting
Description : Scoring is a ________ phenomenon. (a) stick-slip (b) fracture (c) fatigue (d) in-out
Last Answer : (a) stick-slip
Description : Extreme Pressure (EP) additives cause ______ wear in the bearing parts. (a) abrasive (b) corrosive (c) pitting (d) fatigue
Last Answer : (b) corrosive
Description : Scoring is a ________ phenomenon. a) Stick-slip b) Fracture c) Fatigue d) In-out
Last Answer : a) Stick-slip
Description : Propagation of fatigue failure is always due to compressive stresses. a) Due to bending b) Due to tensile c) Due to fatigue d) None of the listed
Last Answer : b) Due to tensile
Description : What will happen if stresses induced due to surge in the spring exceeds the endurance limit stress of the spring. a) Fatigue Failure b) Fracture c) None of the listed d) Nipping
Last Answer : a) Fatigue Failure
Description : The resistance to fatigue of a material is measured by (a) elastic limit (b) Young's modulus (c) ultimate tensile strength (d) endurance limit
Last Answer : (d) endurance limit
Description : Does ASME Standard take into consideration shock and fatigue factors? a) Yes b) No
Last Answer : a) Yes
Description : Calculate fatigue stress concentration factor, when theoretical stress concentration factor is 1.62 and notch sensitivity is equal to 0.9 a. 1.558 b. 3.358 c. 1.162 d. None of the above
Last Answer : a. 1.558
Description : In S-N diagram, the graph plotted between fatigue strength and number of stress cycles becomes horizontal for which type of materials? a. Ferrous materials b. Non-ferrous materials c. Both a. and b. d. None of the above
Last Answer : a. Ferrous materials
Description : Notch sensitivity (q) is given by the equation _______ where K f = fatigue stress concentration factor and K t = theoretical stress concentration factor a. ( K f + 1 ) / ( K t – 1 ) b. ( K f – 1 ) / ( K t – 1 ) c. ( K f + 1 ) / ( K t + 1 ) d. ( K f - 1 ) / ( K t + 1 )
Last Answer : b. ( K f – 1 ) / ( K t – 1 )
Description : There is sufficient plastic deformation prior to fatigue failure, which gives a warning well in advance. a) True b) False
Description : Fatigue failure is time dependent failure. a) True b) False
Last Answer : a) True
Description : 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
Last Answer : b) Fatigue
Description : Deformation that occurs due to stress over a period of time is known as ____________ a) Wear resistance b) Fatigue c) Creep d) Fracture
Last Answer : c) Creep
Description : The notch sensitivity q is expressed in terms of fatigue stress concentration factor Kf and theoretical stress concentration factor Kt as (A) (Kf + 1)/ (Kt + 1) (B) (Kf - 1)/ (Kt - 1) (C) (Kt + 1)/ (Kf + 1) (D) (Kt - 1)/ (Kf - 1)
Last Answer : (B) (Kf - 1)/ (Kt - 1)
Description : The stress which vary from a minimum value to a maximum value of the same nature (i.e. tensile or compressive) is called (a) repeated stress (b) yield stress (c) fluctuating stress (d) alternating stress
Last Answer : (c) fluctuating stress
Description : Under complex loading, principal stresses exist as (a) Firstly σ 1 > σ 2 =σ 3 (b) Secondly σ 1 = σ 2 =σ 3 (c) Thirdly σ 1 > σ 2 < σ 3 (d) None
Last Answer : (d) None
Description : Under complex loading, theories of elastic failure establishes the (a) Margin of failure (b) Margin of safety (c) Both (a) & (b) (d) None
Last Answer : (b) Margin of safety
Description : Under complex loading, theories of elastic failures ensure (a) Stability (b) Instability (c) Both stability and instability (d) None
Last Answer : (a) Stability
Description : Under complex or simple loading, strain energy is (a) External work done (b) Internal work done (c) Both internal and external work (d) None
Last Answer : (b) Internal work done
Description : Under complex loading, if elastic limit reaches in tension, then failure occurs due to (a) Firstly Maximum principal strain theory (b) Secondly Maximum principal theory of strain energy (c) Thirdly Maximum Principal stress theory (d) None
Last Answer : (c) Thirdly Maximum Principal stress theory
Description : Under complex loading, if elastic limit reaches in tension, then failure occurs due to (a) Firstly Maximum principal strain theory (b) Secondly Maximum principal theory of strain energy (c) Thirdly Maximum shear stress theory (d) None
Description : Failure of a material is termed as fatigue failure, if it fails below the yield point. The resistance to fatigue failure of a material is measured by the (A) Ultimate tensile strength (U.T.S.) (B) Endurance limit (C) Elastic limit (D) None of these
Last Answer : (B) Endurance limit
Description : Fatigue limit improvement by over stressing the metal by successively increasing the load is called coaxing. In fatigue failure, the material fails (A) Below the yield point (B) Above the yield point (C) Below the elastic limit (D) At the elastic limit
Last Answer : Option A
Description : Compared to fresh Water, the freezing point of sea water is - (1) Higher (2) Lower (3) Same (4) Depends on the sea from which the water is sourced
Last Answer : (2) Lower Explanation: Ocean water freezes just like freshwater, but at lower temperatures.
Description : The property of the bearing material to yield and adopt its shape to that of journal is called (A) Embeddability (B) Conformability (C) Viscosity (D) Endurance limit stress
Last Answer : (B) Conformability
Description : According to the ASME code, maximum allowable shear stress is taken as X% of yield strength or Y% of ultimate strength. a) X=30 Y=18 b) X=30 Y=30 c) X=18 Y=18 d) X=18 Y=30
Last Answer : a) X=30 Y=18
Description : Line joining S yt (yield strength of the material) on mean stress axis and S e (endurance limit of the component) on stress amplitude axis is called as _____ a. Goodman line b. Soderberg line c. Gerber line d. None of the above
Last Answer : b. Soderberg line
Description : In a ductile material, the strength are (a)Firstly Ultimate >yield > elastic limit (b) Secondly Ultimate > yield =elastic limit (c) Thirdly Ultimate=yield=elastic limit (d) None
Last Answer : (a)Firstly Ultimate >yield > elastic limit
Description : In a brittle material, the strength are (a) Firstly Ultimate >yield > elastic limit (b) Secondly Ultimate > yield =elastic limit (c) Thirdly Ultimate=yield=elastic limit (d) None
Last Answer : (c) Thirdly Ultimate=yield=elastic limit
Description : Theories of elastic failure while dealing with brittle materials consider the failure criterion as (a) Ultimate stress (b) Yield stress (c) Both ultimate and yield stress (d) None
Last Answer : (a) Ultimate stress