Final Exam August $2007$

Question $4$

The composite beam is made of steel $(A)$ bonded to brass $(B)$ and has the cross section shown. If the allowable bending stress for the steel is $({}_{\text{a}\text{l}\text{l}\text{o}\text{w}}{)}_{st}=180$MPa, and for the brass $({}_{\text{a}\text{l}\text{l}\text{o}\text{w}}{)}_{br}=60$MPa, determine the maximum moment M that can be applied to the beam. $E_{br}=100$GPa, $E_{st}=200$GPa.