Material Science (Mixed Bag)

1. Ductility of a material can be defined as

(a) ability to undergo large permanent deformations in compression

(b) ability to recover its original form

(c) ability to undergo large permanent deformations in tension

(d) all of the above

(e) none of the above.

2. Malleability of a material can be defined as

(a) ability to undergo large permanent deformations in compression

(b) ability to recover its original form

(c) ability to undergo large permanent deformations in tension

(d) all of the above

(e) none of the above.

3. In compression, a prism of brittle material will break

(a) by forming a bulge (l>) by shearing along oblique plane

(c) in direction perpendicular to application of load

(d) by crushing into thousands of pieces

(e) none of the above.

4. The ability of a material to resist softening at high temperature is known as

(a) creep

(b) hot tempering

(c) hot hardness

(d) fatigue

(e) super hardening.

5. Mild steel belongs to the following category

(a) low carbon steel

(b) medium carbon steel

(c) high carbon steel

(d) alloy steel

(e) special steel.

6. The ultimate tensile strength of low carbon steel by working at a high strain rate will (a) decrease

(b) increase

(c) remain constant

(d) first increase and then decrease

(e) first decrease and then increase.

7. Slow plastic defoliation of metals under a constant stress is known as

(a) creep

(b) fatigue

(c) endurance

(d) plastic deformation

(e) non-plastic deformation.

8. The ultimate tensile strength and yield strength of most of the metals, when temperature

falls from 0 to l00°C will

(a) increase

(b) decrease

(c) remain same

(d) first increase and then decrease

(e) show unpredictable behaviour.

9. The number of electrons in 1 cm³ of metal would be of the order of

(a) 10¹⁰

(b) 10¹⁰

(c) 10²²

(d) 10⁴⁰

(e) 10⁵²

10. Stress relaxation is- the phenomenon

(a) in which parts are not loaded

(b) in which stress remains constant on increasing load

(c) in which deformation tends to loosen the joint and produces a stress reduced

(d) stress reduces on increasing load

(e) none of the above.

Answer:

    1. c    2. a    3. b    4. c    5. a
    6. b    7. a    8. a    9. c    10. c

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