雷诺数取决于下列哪些因素( )
未知类型：{'options': ['特征尺寸Lc(characteristic length, m)', '流体密度(fluid density, [img=50x27]18033f6a26f2543.png[/img])', '特征速度V(velocity of the bulk fluid, m/s)', '流体的动力粘度μ(dynamic viscosity,kg/(m·s) )'], 'type': 102}
未知类型：{'options': ['特征尺寸Lc(characteristic length, m)', '流体密度(fluid density, [img=50x27]18033f6a26f2543.png[/img])', '特征速度V(velocity of the bulk fluid, m/s)', '流体的动力粘度μ(dynamic viscosity,kg/(m·s) )'], 'type': 102}
举一反三
- 雷诺数取决于下列哪些因素( ) 未知类型：{'options': ['特征尺寸Lc(characteristic length, m)', '流体密度(fluid density, [img=50x27]18033f6a68c3abd.png[/img])', '特征速度V(velocity of the bulk fluid, m/s)', '流体的动力粘度μ(dynamic viscosity,kg/(m·s) )'], 'type': 102}
- 雷诺数取决于下列哪些因素( ) A: 特征尺寸Lc(characteristic length, m) B: 流体密度(fluid density, kg/m3) C: 特征速度V(velocity of the bulk fluid, m/s) D: 流体的动力粘度μ(dynamic viscosity, kg/m·s)
- A compressible fluid is flowing through a pipe with a constriction. The diameter of the narrow section is 1/2 the diameter of the wide section. The density of the fluid in the narrow section is 3/4 the density of the fluid in the wide section. If the velocity of the compressible fluid is 3.600 m/s in the narrow section, then what is the velocity of the fluid in the wide section? A: 0.675 m/s B: 0.805 m/s C: 0.250 m/s D: 0.333 m/s E: 0.500 m/s
- 已知质点沿x轴作直线运动，其运动方程为[img=103x20]17da5d5c7e6b9b5.jpg[/img](SI)，则质点在t=1 s时的速度和加速度为 未知类型：{'options': ['v=8 m/s,a=0', ' v=3 m/s,a=0', ' v=8 m/s,a=-6 m/[img=12x17]17da3b4acc2aeaa.jpg[/img]', ' v=-1 m/s,a=-4 m/[img=12x17]17da3b4acc2aeaa.jpg[/img]'], 'type': 102}
- 铝的介电常数为[img=95x24]17de80759794f2d.png[/img]F/m，电导率为3.82[img=89x24]17de8075a2c149d.png[/img]S/m，则其弛豫时间为（ ）秒 未知类型：{'options': ['', '', '', ''], 'type': 102}