Answer:
i) SF = 0.83
ii) 10 psi
iii) 3.16 psi
iv) 0.0083
Explanation:
Constant load = 1000 Psi
mean resistance = 1200 psi
Probability of failure = 1.9 * 10^-3
Determine
i) Safety factor
S.F = 1 / (mean load / load design ) = 1 / ( 1200 / 1000 ) = 0.83
ii) Standard deviation
1.9 X 10^-3 = e ( -1/2 ( μ / б) ^3 / (2.5 * 6 )
0.004756 = e^- 20000 / б^3
hence std = 10 psi
iii) Variance
= [tex]\sqrt{10}[/tex] = 3.16 psi
iv) coefficient of variation
Cv = std / mean resistance
= 10 / 1200 = 0.0083
