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One (1) multiple choice answer sheet (GPAS-240R)
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Faculty of Science
Page 1 of 38
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Do not write your answers on this page.
Tensile Testing
1. Which one of the following types of stress strain relationship best describes the behaviour of brittle materials such as ceramics and thermosetting plastics:
(a)
(b)
(c)
(d)
elastic and perfectly plastic, elastic and strain hardening, perfectly elastic, or none of the above.
2. Which one of the following types of stress strain relationship best describes the behaviour of most metals at room temperature:
(a)
(b)
(c)
(d)
elastic and perfectly plastic, elastic and strain hardening, perfectly elastic, or none of the above
3. A 100-mm~long steel bar is tested in tension, so that the change in the length is 0.05 mm. If
E 200 GPa, what is the stress developed in the bar?
=
(a)
(b)
(c)
(d)
200 MPa
100 MPa
50 MPa
None of these
4. A steel shaft is subjected to a tensile stress of 500kN. If the shaft has a diameter of 50mm,
what is the stress in the shaft?
(a)
(b)
(c)
(d)
(e)
0.3 MPa .
300 MPa
200 MPa
64 MPa
255 MPa
5. If this steel shaft increases in length by 1mm, what will be the strain on the shaft given the initial length is 1m and E= 200GPa?
(a)
(b)
(c)
(d)
(e)
