【简答题】图所示结构,载荷P=50KkN,AB杆的直径d=40mm,长度l=1000mm,两端铰支。已知材料E=200GPa,σ p =200MPa,σ s =235MPa,a=304MPa,b=1.12MPa,稳定安全系数n st =2.0,[σ]=140MPa。试校核AB杆是否安全。
【简答题】任务型阅读理解:仔细阅读下面的短文并按要求完成后面的小题。 We are in a world full of competition. Our parents compete with others in their offices, our brothers and sisters compete with others in their colleges, (1)and we compete...