Two solid cylinderical rods AB & BC are welded together at B & loaded as shown. Knowing that d(1)=30mm & d(2)=50mm, find the average normal stress in the midsection of (a)rod AB, (b) rod BC.(adsbygoogle = window.adsbygoogle || []).push({});

B____________C

125kN--->| |

A______________| |

60kN<---| | |

| | |

|______________| |

|<- 0.9m------>| |

125kN--->|____________|

|<---1.2m--->|

stress = P/A

(a) A= pie r ^2=pie (30mm/2)^2=.000707 m^2

stress=P/A= (60x10^3 N)/(.000707)=84.9MPa

(b) A= pie r^2)= pie(50mm/2)^2=.001963

stress= P/A= (250x10^3)/.001963=106.1 MPa

the stress for (b) is wrong; it's suppose to be 96.8MPa Can someone show me what I have done wrong and explain why it should be done differently? Thanks

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# Homework Help: Average normal stress

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