15.  Factor of safety is the ratio of
A. yield stress to working stress
B. tensile stress to working stress
C. compressive stress to working stress
D. bearing stress to working stress

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16.  Assuming the values of maximum deviation AP and AE to be 25% of the computed value of P and]? respectively, the minimum value of the factor of safety is
A.1
B.0.67
C.1.67
D.2.67

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17. The ratio of longitudinal stress' to strain within elastic limit, is known as
A. modulus of elasticity
B. shear modulus of elasticity
C. bulk modulus of elasticity
D. tangent modulus of elasticity which a structural member

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18.  The ratio of shearing stress to shearing strain within elastic limit, is known as
A. modulus of elasticity
B. shear modulus of elasticity
C. bulk modulus of elasticity
D. tangent modulus of elasticity

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19. The ratio of hydrostatic stress to the volumetric strain within the elastic range, is called
A. modulus of elasticity
B. shear modulus of elasticity
C. bulk modulus of elasticity
D. all the above.

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20. Poisson's ratio for steel within elastic limit, ranges from
A. 0.15 to 0.20
B. 0.25 to 0.24
C. 0.25 to 0.33
D. 0.33 to 0.35

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21.  The rivets which are heated and then driven in the field, are known
A. power driven shop rivets
B. power driven field rivets
C. hand driven rivets
D. cold driven rivets

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