新概念物理教程 力学答案详解(五)

新概念物理教程 力学 答案 八年级地理上册填图题岩土工程勘察试题省略号的作用及举例应急救援安全知识车间5s试题及答案 详解(五) 新力学习 题 快递公司问题件快递公司问题件货款处理关于圆的周长面积重点题型关于解方程组的题及答案关于南海问题 答案(五) 5—1(如本题图所示为圆筒状锅炉的横截面，设气体压强为p，求壁内的正应力。已知锅炉直径为D，壁厚为d(D>>d)，应力在壁内均匀分布。 df,`解:,,,p,ds 5—2((1)矩形横截面杆在轴向拉力的作用下产生拉伸应变为,，此材料的泊松比为,，求证体积的相对改变为: VV,0，，,1,2,,V0 式中V和V分别代表原来和形变后的体积。0 (2)式中是否适用于压缩, 103)低碳钢的杨氏模量为Y(=19.6*10Pa,泊松比为0.3,受到的拉应力为,=1.37Pa,求杆体积的相对改变。 解:()证明:1,,,,l,,,l,l(a)0l0,,,,,,d横,？又,,？,d,d0横d0,,,2222，，，，，，，，V,ldV,l，,ld,,d,1，l1,d0000000,,, ，，，,1，,2V0 ,,V,V0，，？,1,2V0,，，压缩时:(2)l,l,,l,1,l00,,，，d,d，,d,1，d00 2,,,,,,2，，，，，，，，，V,ld,1,l1，d,1,，2V000 V,V0,,，，？,,1,2V0 所以上式仍适用，不过比值变为负值 ,,l,,,()3,Y,Y？,lY0 V,V,1.37,120，，，，，，,1,2,1,2,1,2，0.3,2.8，10,,,10VY19.6，100 administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel welding procedures of steel pressure vessel NDT 9 JB/T4744-2000 steel pressure vessel products mechanical properties test of welded plate II, mechanical equipment installation engineering 1 GB150-98 2 GB50128-2005 vertical cylindrical steel pressure vessel steel welded tank code for construction and acceptance of 3 JB/ T4735-1997 steel welded atmospheric pressure vessel 4 GB50231-2009 mechanical equipment installation engineering construction and acceptance specification for 5 GB50275-98 compressor, fan and pump installation engineering construction and acceptance specification for lifting 6 5—3(在剪切钢板时，由于刀口不快，没有切断，该材料发生了剪切形变。钢板的横截面积 25为S=90cm，二刀口间的距离为d=0.5cm，当剪切力为F=7*10N时，已知钢板的剪变模量 10为G=8*10Pa，求: (1)钢板中的剪切应力; (2)钢板的剪切应变; (3)与刀口齐的两个截面所发生的相对滑移。 5F7，1078//,1,,,，10Pa解:()//,4S990，10 78，10,7,29//,,,(2),G,,,,，10//10G728，10 ,d77,2,2(3,),,,d,,d,，10，0.5,，10cmd721445—4(矩形横截面边长2:3的梁在力偶矩作用下发生纯弯曲。对于截面的两个不同取向，同 样的力偶矩产生的曲率半径之比为多少, 解:依据梁弯曲的曲率半径公式，有: 3YbhR,12M外 23aa设边长分别为与 b,2ah,3a一种取向: 34Y2a3a52Ya，，R,,(1)则:112M12M外外 b,3ah,2a另一种取向: 34Y3a，，2a24YaR,,(2)则:212M12M外外 R5491？,,244R2 5—5(试推导钢管扭转常量D的表达式。 解:钢管中间是空的。 lRR设钢管长度为，管内外半径分别为与。12 ,当钢管有一个角的扭转角时，对于R,r,R在半径r处任一点产生的,12 ,r,,rr偎依为？剪变角为,，，l ,Gr,,Gr剪切应力,,，，//l ,rrdrdsrdr在,，的面积,2 2Grdr2,,？dr内剪切力为df,ds,,//l administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel welding procedures of steel pressure vessel NDT 9 JB/T4744-2000 steel pressure vessel products mechanical properties test of welded plate II, mechanical equipment installation engineering 1 GB150-98 2 GB50128-2005 vertical cylindrical steel pressure vessel steel welded tank code for construction and acceptance of 3 JB/ T4735-1997 steel welded atmospheric pressure vessel 4 GB50231-2009 mechanical equipment installation engineering construction and acceptance specification for 5 GB50275-98 compressor, fan and pump installation engineering construction and acceptance specification for lifting 6 3,,2Grdr此力对主轴的力矩为dM,rdf,l 3,,,,R2GrdrG244,，，？M,dM,,R,R,D21,,R1ll2 ,G44，，？D,R,R212l 5—6(一铝管直径为4cm,壁厚1mm,长10m,一端固定，另一端作用一力矩50N.m，求铝管 10的扭转角,。对同样尺寸的钢管再计算一遍。已知铝的剪变模量G=2.65*10Pa，钢的剪变模10量为8.0*10Pa.。 M,解:依5—5题有:,,,G44，，R,R212l 代入数据即可(略) 5—7(用流体静力学基本原理，论证液面上有大气、物体全部浸在液体中的情况下的阿基米德原理。 h1解:取物体内面积为ds(设其在水平方向的投影为ds*)的小柱体，小柱体的上下地面距离水面分别为h与h12 则:这部分小柱体受到的浮力为: ,,h，，，，df,Pds*,Pds*,P，ghds*,P，ghds*20201浮下底上底 ,,，，,,,ghhds*gdV21 (dV是小柱体的体积) ？f,df,,gdV,,gV浮浮物,,325—8(灭火筒每分钟喷出60m的水，假定喷口处水柱的截面积为1.5cm，问水柱喷到2m 高时其截面积有多大, 解:设喷口处为1处，水柱喷到2m处为2处 依伯努力方程有: 1122P，v,P，gh，v(1),,,112222 P,P,P(2)120 603Q,vs,vs,,1m/s(3)1122V60 1124:v,,,，10m/s有以上三式得1,4s31.5，101 4283v,v,2gh,，10,2，10，2,2.11，10m/s219 1,422s,,4.7，10m,4.7cm2v2 administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel welding procedures of steel pressure vessel NDT 9 JB/T4744-2000 steel pressure vessel products mechanical properties test of welded plate II, mechanical equipment installation engineering 1 GB150-98 2 GB50128-2005 vertical cylindrical steel pressure vessel steel welded tank code for construction and acceptance of 3 JB/ T4735-1997 steel welded atmospheric pressure vessel 4 GB50231-2009 mechanical equipment installation engineering construction and acceptance specification for 5 GB50275-98 compressor, fan and pump installation engineering construction and acceptance specification for lifting 6 5—9(一截面为5.0cm2的均匀虹吸管从容积很大的容器中把水吸出。虹吸管最高点高于水 面1.0m，出口在水下0.6m处，求水在虹吸管内作定常流动时管内最高点的压强和虹吸管的 体积流量。 解:设水面为处，最高点为处，出口处为处以处为基准123,1依伯努力方程有: ,,,,,111222P，v,P，gh，v,P，gh，v11222333222其中:可看作，忽略不计P,P,Pv01301 定常流动:v,v,v23 h,1.0mh,,0.6m23 11,,,,22所以，由上式可变为:P，gh，v,P，gh，v22233322 1122,,,,P，gh，v,P，gh，v220322 最高点的压强为:？ 534,，，，，P,P，gh,h,1.01，10，10，10,0.6,1.0,8.5，10Pa2032 1122由,,,得:P，v,P，gh，v1133322 v,,2gh,2,10，0.6,23m/s33 ,433？Q,vs,23，5.0，10,1.73，10m/s33V 25—10(油箱内盛有水和石油，石油的密度为0.9g/cm，水的厚度为1m，油的厚度为4m。 求水自箱底小孔流出的速度。 解:设油与大气的接触面为处，油与水的接触面为处，小孔为处123,则:P,P,PP,P，gh13021油油 为要求的速度v,v,0v123 以小孔处为高度点0 依伯努力方程有: 12,,P，gh,P，v233水水水2 ,，，2P，gh,P，，2P,P00油油23？v,，2gh,，2gh3水水,,水水 ,2gh2*900*10*4油油,，2gh,，2*10*1,92,9.6m/s水,1000水 administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel welding procedures of steel pressure vessel NDT 9 JB/T4744-2000 steel pressure vessel products mechanical properties test of welded plate II, mechanical equipment installation engineering 1 GB150-98 2 GB50128-2005 vertical cylindrical steel pressure vessel steel welded tank code for construction and acceptance of 3 JB/ T4735-1997 steel welded atmospheric pressure vessel 4 GB50231-2009 mechanical equipment installation engineering construction and acceptance specification for 5 GB50275-98 compressor, fan and pump installation engineering construction and acceptance specification for lifting 6 5—11(一截面为A的柱形桶内盛水的高1度为H，底部有一小孔，水从这里流出。设水柱的最小截面积为S，求容器内只剩下一半水和水全部流完所需的时间t和t。 12解:由于随着水的高度的变化，从桶底流出的水的速度不同，所以在hdt时间内流出的水dQ,vsdt,AVdt,Adh也不同，故用积分形式求解。V 设在t时刻，水面距桶底的高度为h，dt时间内水面下降dh 11,,2,2依伯努力方程有:，，,，PghVPv0022 vs又:VA,vs,V,A 21vs1,,2,,,？上式变为:gh，,v,,2A2,, 2A,v,2gh22A,s 2A又依连续性方程有:Adh,vsdt,2ghsdt22A,s dh上式变形得:,sdt(1) 2gh 22A,s H若只剩一半水，从()式两边积分:hH,,12 22H/2t，，12,dhAsH1,,sdt？t,(H,)1,,H0sg22gh 22A,s 若全部流完，则从()式两边积分:hH,0,1 220t，，12,dhAs2,,sdt？t,H2,,H0sg2gh 22A,s 5—12(在一20cm*30cm的矩形截面容器内盛有深度为50cm的水。如果从容器底部面积为 22.0cm的小孔流出，求水流出一半时所需的时间。 511解:由—的答案得: 2A,0.2，0.3,0.06m 2222,812A,sH10.06,2.0，10，，，，t,(H,),0.5,0.25，，,4sg2102.0，10 ,0.19s administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel welding procedures of steel pressure vessel NDT 9 JB/T4744-2000 steel pressure vessel products mechanical properties test of welded plate II, mechanical equipment installation engineering 1 GB150-98 2 GB50128-2005 vertical cylindrical steel pressure vessel steel welded tank code for construction and acceptance of 3 JB/ T4735-1997 steel welded atmospheric pressure vessel 4 GB50231-2009 mechanical equipment installation engineering construction and acceptance specification for 5 GB50275-98 compressor, fan and pump installation engineering construction and acceptance specification for lifting 6 5—13(如图5—35a所示，在一高度为H的量筒侧壁上开一系列高度h不同的小孔。试证 明:当h=H/2时水的射程最大。 解:设A为量筒截面面积，s为小孔面积 V为液面水的速度，v为高度h处从小孔流出的水的速度依伯努力方程有: 1122,,,,P，gH，V,P，gh，v0022 又依连续性原理有:VA,vs 2A，，？v,2gH,h22A,s 12设水到达地面时所需的时间为t,则:y,h,gt2 t,2gh 2A1，，射程:x,vt,2gH,h2gh,2gAh(H,h)2222A,sA,s 21HH,,,2gA,h,，,,2224A,s,, H？当h,时,射程x最大2 5—14(推导文丘里流量计的流量公式。 解:文丘里流量公式是: ,,1122P，v,P，v(h,h)在水平流管满足即的前提下，有11221222 2,PQ,vs,ssV1112,22，，s,s12 11,22,,2,,，,，PvPvs1,112221,,,证明:,v1,,P,P22,1212,,2s2,,,vs,vs1122, 2，，，，,,2PPs2PP12,P121221？v,,s,12222222,,,s,ss,ss,s212121 2P,Qvsss,,,V111222，，,s,s12 administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel welding procedures of steel pressure vessel NDT 9 JB/T4744-2000 steel pressure vessel products mechanical properties test of welded plate II, mechanical equipment installation engineering 1 GB150-98 2 GB50128-2005 vertical cylindrical steel pressure vessel steel welded tank code for construction and acceptance of 3 JB/ T4735-1997 steel welded atmospheric pressure vessel 4 GB50231-2009 mechanical equipment installation engineering construction and acceptance specification for 5 GB50275-98 compressor, fan and pump installation engineering construction and acceptance specification for lifting 6 5—15(在盛水圆筒侧壁上有高低两个小孔，它们分别在水面之下25cm和50cm处。自它们 设出的两股水流在哪里相交, 解:为简单起见，设圆筒截面远大于小孔截面设在水面下h处的速度为v 12,,依伯努力方程有:P，gh,P，v,v,2gh002 经时间t后水的射程为x“射高”为,y,则: 12y2y,gt,t,2g ？x,vt,2hy h,0.25mh,0.5m12 相遇时有:x,x12 ？hy,hy即y,2y(1)112212 又:y,y,h,h,,0.25(2)1221 由(1)(2)得:y,0.5my,0.25m12 ？x,x,20.25，0.5,0.71m12 5—16(如本题图，A是一个很宽阔的容器，B是一根较细的管子，C是压力计。 (1)若拔去B管下的木塞，压力计的水位将处在什么地方, (2)若B管是向下渐细的，答案有何改变, 解:(1) 分析 定性数据统计分析pdf销售业绩分析模板建筑结构震害分析销售进度分析表京东商城竞争战略分析 、交接处，根据水平管的特点:BC 1122管内等高处有:PvPv，,，,,BBCC22 ssvvPP,？,,,CBBCBC 所以压力计的水位将处于的水位之下。A (2) administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel welding procedures of steel pressure vessel NDT 9 JB/T4744-2000 steel pressure vessel products mechanical properties test of welded plate II, mechanical equipment installation engineering 1 GB150-98 2 GB50128-2005 vertical cylindrical steel pressure vessel steel welded tank code for construction and acceptance of 3 JB/ T4735-1997 steel welded atmospheric pressure vessel 4 GB50231-2009 mechanical equipment installation engineering construction and acceptance specification for 5 GB50275-98 compressor, fan and pump installation engineering construction and acceptance specification for lifting 6 25—17(一桶的低部有一洞，水面距桶底30cm，当桶以120m/s的加速度上升时，水自洞漏出的速度为多少, 解:以桶为参考系，由小洞流出的水不仅受重力作用，还受惯性力作用。所以，这里的伯努力方程中的g,g，a 12？P，g，ah,P，v，，,,002 ，，，，？v,2g，ah,2，10，120，0.3,78,8.8m/s 又刚开始时v,0,所以v,8.8m/s就是所求。桶 y x5—18(如本题图，方新形截面容器侧壁有一小孔，其下缘的高度为h。将孔封住时，容器内液面高度达到H，此容器具有怎样的水平加速度a，即使将孔打开，液体也不会从孔中流出,此时液面是怎样的, a解:先求容器无水平加速度时小孔处的液体l F受到容器内液体的作用力: 依伯努力方程知小孔处液体的速度v为:H ，，,,v2gHhh,,，，，，？F,Qv,0,vsv,s2gH,h(向右)m ma,F要使水不流出，必需有一个向左的力 ,,，，，，FsgH,hsgH,h22？a,,,,mQsvm 2，，,gH,hms2/ a的方向水平向右 dm此时的液面:在液面上取的液体，以容器为参考系: 该液体受重力、惯性力以及支持力的作用，三力平衡，所以有: ，，2gH,hdyadm,,,,切线的斜率:tandxgdmg ，，,Hh2？y,x，x(直线)0g 即液面是斜面的形状。 5—19(使机车能在行进时装水，使用的装置如本题图所示，顺着铁轨装一长水槽，以曲管引至机车上。曲管之另一端浸入水槽中，且其开端朝向运动的前方。试计算，火车的速度多大，才能使水升高5.1m, 解:由题意知:流入曲管的水的速度(也是相对水槽的速度)就是火车的速度。 依伯努力方程有: administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel welding procedures of steel pressure vessel NDT 9 JB/T4744-2000 steel pressure vessel products mechanical properties test of welded plate II, mechanical equipment installation engineering 1 GB150-98 2 GB50128-2005 vertical cylindrical steel pressure vessel steel welded tank code for construction and acceptance of 3 JB/ T4735-1997 steel welded atmospheric pressure vessel 4 GB50231-2009 mechanical equipment installation engineering construction and acceptance specification for 5 GB50275-98 compressor, fan and pump installation engineering construction and acceptance specification for lifting 6 1,2P，v,P，gh,,,AB,v,2gh,2，9.8，5.1,10.0m/s2, ,P,P,PAB0, 5—20(试作下击式水轮机最大功率和转速的计算。如本题图所示，设水源高h=5m，水流 2截面积s=0.06m，轮的半径R=2.5cm;还不假定水连续不断地打在浆叶上，打击后水以浆液的速度流去。 解:依伯努力方程有:水从截面出来时的速度为v,2gh ,, Q,vs,s2ghm 水与浆叶相撞，角动量守恒: ,,,QvR,I，Qv',I，QRmmm 又:(浆质量集中与中心上)I,0 由此看来，无能量损失，所以求出的转速与功率为最大值。nP 2ghv2，10，52,弧秒？,,,,4，10/RR0.025 2,4，10n,,,63.7r/s,22，3.14 12,mv113/222，，无能量损失,:P,,Qv,s2ghm,t22 13/234，，,，10，0.06，2，10，5,3.0，10J2 20—21(在一截面积为50cm5的水管上接有一端弯管，使管轴偏转75。设管中水的流速为3.0m/s。计算水流作用在弯管上力的大小和方向。 , v,3.0m/s1 075解:水流作用在弯管上的力等于单位时间内,v,3.0m/s水流的动量的减少量，即:2,,,,,,，，，，F,Qv,v,vsv,vm1212 如图: 203,，，力的大小:F,vs2vsin75/2,10，2，0.005，3.0， , 力的方向:与水平夹角为,，tan,, administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel welding procedures of steel pressure vessel NDT 9 JB/T4744-2000 steel pressure vessel products mechanical properties test of welded plate II, mechanical equipment installation engineering 1 GB150-98 2 GB50128-2005 vertical cylindrical steel pressure vessel steel welded tank code for construction and acceptance of 3 JB/ T4735-1997 steel welded atmospheric pressure vessel 4 GB50231-2009 mechanical equipment installation engineering construction and acceptance specification for 5 GB50275-98 compressor, fan and pump installation engineering construction and acceptance specification for lifting 6 5—22(在重力作用下，某液体在半径为R的竖直圆管中向下作定常层流，已知液体的密度为,，测得从管中流出的体积流量为Q，求 (1)液体的粘滞系数,; (2)管轴处的流速,。 解:该圆管是竖直放置的。可参照泊萧叶公式的推导过程求解。 labrrdr在圆管内取,长的一端，取,，的小圆管，以流速方向为正向，则有:,, ,dv,,f,,2rl,,r,dr,,,r,,,dv,,,，，f,2r，drl,,，rdr,dr,,，rdr, ,,,,ddv,,？f,f，f,2l,r,dr,,，rrdr,,drdr,,,,, 此力应与端面2rdr上的压力差及该小圆管的重力平衡: ,,,,,,ddv,,，，P,P2rdr,l2rdrg,f,2l,r,dr,,ba,,drdr,,,,,PPgl,，22ab，，，，经两次积分得:vr,R,r,4l ,,RP,P，gl,4ab，，Q,vds,2vrrdr,R,V,,08l ,,低速情况下:P,P,gh,glab ,,g4？Q,Q,RV,4 ,,g4,(1),,R4Q 2,,ggR4Q2Q22，，，，(2)管轴处的速度(r,0处):vr,0,R,0,,422,2，gRR,,,5—23(粘滞流体在一对无限大平行平面板之间流动。试推导其横截面上的速度分布公式。 解:如图所示，以中心轴为x轴，建立如图所示的 y 坐标系，在y+dy之间取一面积为,s,宽为dy 的流体。 设v沿正x 方向，分析其受力: y，dy y O x administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel welding procedures of steel pressure vessel NDT 9 JB/T4744-2000 steel pressure vessel products mechanical properties test of welded plate II, mechanical equipment installation engineering 1 GB150-98 2 GB50128-2005 vertical cylindrical steel pressure vessel steel welded tank code for construction and acceptance of 3 JB/ T4735-1997 steel welded atmospheric pressure vessel 4 GB50231-2009 mechanical equipment installation engineering construction and acceptance specification for 5 GB50275-98 compressor, fan and pump installation engineering construction and acceptance specification for lifting 6 ,,dv,在处:,,yf,,sy,,dy,,y ,,dv,在处:,,y，dyf,,,sy，dy,,dy,,y，dy 体积的两头截面所在高度相等，无压强差，,sdy ,,,,dvdv0,,,,(常量)？f，f,,,,Cyy，dy,,,,dydy,,,,yy，dy ，，？vy,Cy，A 设两平面之间的距离为2,则有:(0),()0av,Ava, 0？,ca，A vA中心(0),A,v,vc,,,,中心aa v中心()？vy,,y，Aa35—24(密度为2.56g/cm、 直径为6.0mm的玻璃在一盛甘油的筒中自静止下落。若测得小 3球的恒定速度为3.1cm/s，试计算甘油的粘滞系数。甘油的密度为1.26g/cm。 解:依斯托克斯公式有: 432,,rg2,21求2gr,mg2，2.56，9.8，10，，，6.0，10求3,,,,,6rv6rv9v9，3.1,, ，，,65g/cm,s,6.5kg/m,s,6.5Pa.s 335—25(一半径为0.10cm的小空气泡在密度为0.72*10kg/m、粘滞系数为0.11Pa.s的液体中上升，求其上升的终极速度。 解:依斯托克斯公式有: 43,,rg22空,2grmg2，1.3，0.001，9.8，，3空v,,,,6r6r99，0.11,,,,, ,5,2.58，10m/s -3-25—26(试分析计算半径为1.0*10mm和5.0*10mm的雨滴的终极速度。已知空气的粘滞-5-33系数为1.81*10Pa.s，密度为1.3*10g/cm。 administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel welding procedures of steel pressure vessel NDT 9 JB/T4744-2000 steel pressure vessel products mechanical properties test of welded plate II, mechanical equipment installation engineering 1 GB150-98 2 GB50128-2005 vertical cylindrical steel pressure vessel steel welded tank code for construction and acceptance of 3 JB/ T4735-1997 steel welded atmospheric pressure vessel 4 GB50231-2009 mechanical equipment installation engineering construction and acceptance specification for 5 GB50275-98 compressor, fan and pump installation engineering construction and acceptance specification for lifting 6 依斯托克斯公式有: 43,,rg2空,2grmg空3v,,,,,,,,6r6r9 ,5,4,,1.81，10Pa.s,1.81，10g/cm.s ,3半径为1.0，10mm时: 2,3,52，，2，1.3，10，1.0，10，9.8，10,7v,,1.5，10cm/s1,49，1.81，10 ,2半径为5.0，10mm时: 2,3,42，，2，1.3，10，5.0，10，9.8，10,4v,,3.75，10cm/s2,49，1.81，10 administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel welding procedures of steel pressure vessel NDT 9 JB/T4744-2000 steel pressure vessel products mechanical properties test of welded plate II, mechanical equipment installation engineering 1 GB150-98 2 GB50128-2005 vertical cylindrical steel pressure vessel steel welded tank code for construction and acceptance of 3 JB/ T4735-1997 steel welded atmospheric pressure vessel 4 GB50231-2009 mechanical equipment installation engineering construction and acceptance specification for 5 GB50275-98 compressor, fan and pump installation engineering construction and acceptance specification for lifting 6