In a notched tensile fatigue test on a titanium specimen, the expected number of cycles to first acoustic emission (used to indicate crack initiation) isu =the standard deviation of the number of cycles is o28,000, and4000. Let X,, X, . . . , X25 be a random sample of size 25, where each X; is the number of cycles on a differentExample 5.242'randomly selected specimen. Then the expected value of the sample meannumber of cycles until first emission is E(X)28,000, and the expected total= U =number of cycles for thearespecimens is E(T,) = nµ = 25(28,000) = 700,000. The standard deviations of X and T,ox = 0/VnVV 25(4000) =no =If the sample size increases to n = 100, E(X) is unchanged but o ,= 800half of its previous value (the sample size must be quadrupled vtohalve the standard deviation of X.)

Given,E(x) = μ=28000SDσ = 4000 n = 25

In a notched tensile fatigue test on a titanium specimen, the expected number of cycles to first acoustic emission (used to indicate crack initiation) is u = 28,000, and the standard deviation of the number of cycles is o = 4000. Let X,, X, ...,X5 be a random sample of size 25, where each X, is the number of cycles on a different randomly selected specimen. Then the expected value of the sample mean v number of cycles until first emission is E(X) = µ = 28,000, and the expected total number of cycles for the specimens is E(T,) = nụ = 25(28,000) = 700,000. The standard deviations of X and T, are Vn = Vno = /25(4000) = If the sample size increases to n = 100, E(X) Is unchanged but o = 800 x , half of its previous value (the sample size must be quadrupled v to the ctandard devlation of

In a notched tensile fatigue test on a titanium specimen, the expected number of cycles to first acoustic emission (used to indicate crack initiation) is u = 28,000, and the standard deviation of the number of cycles is o = 4000. Let X,, X, ...,X5 be a random sample of size 25, where each X, is the number of cycles on a different randomly selected specimen. Then the expected value of the sample mean v number of cycles until first emission is E(X) = µ = 28,000, and the expected total number of cycles for the specimens is E(T,) = nụ = 25(28,000) = 700,000. The standard deviations of X and T, are Vn = Vno = /25(4000) = If the sample size increases to n = 100, E(X) Is unchanged but o = 800 x , half of its previous value (the sample size must be quadrupled v to the ctandard devlation of

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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