【单选题】一圆轴的横截面是外径为D、内径为d的空心轴,且a=d/D,则其极惯性矩和抗扭截面系数应为( )。
【判断题】一内径为d,外径为D的空心圆截面轴,其极惯性矩可由式 计算,而抗扭截面系数则相应地可由式 计算。( )
【判断题】一内径为d,外径为D的空心圆轴截面轴,其极惯性矩可由式【图片】计算,而抗扭截面系数则相应地可由式【图片】计算。
【判断题】一内径为d,外径为D的空心圆轴,其极惯性矩可由式 计算,而则相应的抗扭截面系数可由式 计算。
【判断题】一内径为d,外径为D的空心圆轴截面轴,其极惯性矩可由式Ip ≈ 0.1(D4 - d4)计算,而抗扭截面系数则相应地可由式Wt ≈ 0.2(D 3- d3)计算。
【单选题】物体的主视图反映物体的()相对位置关系。
【单选题】Speaker A: Well, I'm really glad I talked to Doug about the problem I was having with my girlfriend. He gave me some excellent advice. Speaker B: Great. That's what I like about Doug. ______, and he's...
B.
He is a really good listener
C.
He is really easy-going