machine design

1. KRISHNA ENGINEERING COLLEGE, GHAZIABAD 9952284510
MACHINE DESIHN-1
PRACTILE QUIZ
TIME – 15 min. Max. Marks- 20
1. The ultimate strength of steelin tension in comparison to shear is in the ratio of
(a) 1: l
(b) 2:1
(c) 3: 2
(d) 2: 3
(e) 1: 2
2. The pci Tnissible stress for carbon steelunder static loading is generally taken as
(a) 2000-3000 kg/pm2
(b) 3000-4000 kg/cm2
(c) 4000-J500 kg/cm2
(d) 7500-10,000 kg/cm2
(e) 10,000-15,000 kg/cm2.
3. The property of a material which enables it to resist fracture due to high impact loads is known as
(a) Elasticity
(b) Endurance
(c) Strength
(d) Toughness
(e) Resilience.
4. A hot short metal is
(a) Brittle when cold
(b) Brittle when hot
(c) Brittle under all conditions
(d) Ductile at high temperature
(e) Hard when hot.
5. Guest's theory of failure is applicable for following type of materials
(a) brittle
(b) ductile
(c) elastic

2. (d) plastic
(e) tough.
6. Rankine's theory of failure is applicable for following type of materials
(a) brittle
(b) ductile
(c) elastic
(d) plastic
(e) tough.
7. 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
(e) none of the above.
8. Resilience of a material is important, when it is subjected to
(a) combined loading
(b) fatigue
(c) thermal stresses
(d) wear and tear
(e) shock loading.
9. 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
(e) none of the above.
10. .Other method of reducing shock load in the above case can be
(a) to decrease length
(b) to increase length
(c) unaffected by length
(d) other factors would decide same
(e) none of the above.

3. 11. Brittle coating technique is used for
(a) determining brittleness
(b) protecting metal against corrosion
(c) protecting metal against wear and tear
(d) experimental stress analysis
(e) non-destructive testing of metals.
12. 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
(e) none of the above.
13. The endurance limit of a material with finished surface in comparison to rough surface is
(a) more
(b) less
(c) same
(d) more or less depending on quantum of load
(e) unpredictable. Ans: a
14. Plastic flow in ductile materials
(a) increases the seriousness of static loading stress concentration
(b) lessens the seriousness of static loading stress concentration
(c) has no effect on it
(d) depends on other considerations
(e) none of the above.
15. The maximum stress due to stress concentration in a bar having circular transverse hole, as
compared to its static stress without hole will be
(a) same in both cases
(b) 2 times more
(c) 3 times more
(d) 4 times more
(e) unpredictable.

4. 16. The fatigue life of apart can be improvedby
(a) electroplating
(b) polishing
(c) coating

5. (d) shotpeening
(e) heattreating.
17. Stressconcentrationinstaticloadingismore seriousin
(a) ductile materials
(b) brittle materials
(c) equallyseriousinbothcases
(d) dependsonotherfactors
(e) unpredictable.
18. Stressconcentrationincyclicloadingismore seriousin
(a) ductile materials
(b) brittle materials
(c) equallyseriousin bothcases
(d) dependsonotherfactors
(e) unpredictable.