【单选题】下列______可作为管内流体流动流向判据。
【判断题】管内流体的流动速度越快,管道的流动阻力损失越大。
【单选题】听力原文:M: Hi, Linda. W: Hi, James. What am you doing in the mall? I thought you said you avoid these places and here you arc. M: Oh, I still do but it's my roommate's birthday tomorrow and I am looking ...
A.
In a mall outside a clothing store.
B.
In a mall inside a clothing store.
【简答题】流体在管内作湍流流动时,从中心到壁可以__________.___________._______________.
【判断题】流体做稳定流动时,流管内外的流体不能穿过流管侧壁进行交换。( )
【单选题】听力原文:M: Hi, Linda. W: Hi, James. What are you doing in the mall? I thought you said you avoid these places. M: Oh, I still do, but it's my roommate's birthday tomorrow and I am looking around to get h...
【单选题】“管内各截面处的体积流量相等”,此话适用于( )A、定态流动 B、管内流体流动的任何情形 C、不可压缩流体流动 D、不可压缩流体定态流动
【单选题】(2004年第一大题第25小题)在下列各项资金时间价值系数中, 与资本回收系数互为倒数关系 的是( )。
【单选题】花生最易受到()污染而出现食品卫生学问题。
【单选题】花生最易受到( )污染而出现食品卫生学问题。