制动装置的杠杆用直径[tex=4.0x1.0]fj+o1uGKNdNjk2PHhIRkFJUK64id5/AE+D7NgPCrH3M=[/tex]的销钉支承在 $B$ 处。若杠杆的许用应力[tex=5.5x1.357]9qhyrC5NEKt4WkwZK7CS1LvAmJ6f7dfuH6GEn5VAerc=[/tex], 销钉的剪切许用应力[tex=5.357x1.357]G0WVEpmkXOaCLIuFKm+WuybU47yx5x6dLS7KR6eFP/8=[/tex], 求许可载荷 [tex=4.643x1.357]pQbquBu1TRiZU4DFRuBX7IpOIH0NDQNKVy6zpm4umO5yFKbX78xypVMLOoE6rX56Gwe+wMc9q/yrbaZAJN0MiGB77Vz1pcC5hCyaXn2iyE8owsNYdzTEWBvVEkxDma4x[/tex]。[img=555x218]17a961bfa19e11e.png[/img]

2022-05-26

制动装置的杠杆用直径[tex=4.0x1.0]fj+o1uGKNdNjk2PHhIRkFJUK64id5/AE+D7NgPCrH3M=[/tex]的销钉支承在 $B$ 处。若杠杆的许用应力[tex=5.5x1.357]9qhyrC5NEKt4WkwZK7CS1LvAmJ6f7dfuH6GEn5VAerc=[/tex], 销钉的剪切许用应力[tex=5.357x1.357]G0WVEpmkXOaCLIuFKm+WuybU47yx5x6dLS7KR6eFP/8=[/tex], 求许可载荷 [tex=4.643x1.357]pQbquBu1TRiZU4DFRuBX7IpOIH0NDQNKVy6zpm4umO5yFKbX78xypVMLOoE6rX56Gwe+wMc9q/yrbaZAJN0MiGB77Vz1pcC5hCyaXn2iyE8owsNYdzTEWBvVEkxDma4x[/tex]。[img=555x218]17a961bfa19e11e.png[/img]

答案：

解：（1）求 [tex=1.571x1.214]mv3CtJ4McQnI3XmnjfLaDLdPqPWuV9HpRTtgQOAYUSo=[/tex]与[tex=1.571x1.214]mv3CtJ4McQnI3XmnjfLaDJFNFLyvu9NZ8KAslKDZhYw=[/tex]的关系杠杆平衡时有: [tex=14.786x1.214]mhybWCGFCP49vM8khNShi41EwoJq2GaZa89Ia2sYo6mr7c9V0C84YKRAWnfCuf49iefvM9ZCxP4sCQ+jz3v4zIMT1LkXm4vUrz323+rNtBdBkLNpV3NZeUz8LKX2pjdejKJc4m1VqqicSC5ZYr43EQ==[/tex]（2）作弯矩图, 如图 a 所示[img=427x598]17a961cfeacb863.png[/img]（3）梁的弯曲正应力强度条件[tex=16.714x12.071]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[/tex][color=#000000]（4）校核销钉的剪切强度  [/color][color=#000000]剪切强度条件： [/color][color=#000000][/color][tex=6.5x2.429]GasNvsHkKDpvpbHaoV9G7ZqOHbAJRWKHUp9npu+JjJYU8rYfd8eeqabrbdB2+/G+[/tex]其中,[tex=9.643x2.357]nXmcKW5uTrbtK/tkF/tNHOkYAzdWRxA/w8Sj1+qofknTUSg4W9utYJIOuYCgqnX1j4pQ/SxDYyCRKYtfsk3fxQ==[/tex][color=#000000][/color][tex=14.929x2.5]hXC3wYo/2U+X8w6dMFjniZzKJent3guMmVpinM29usnGpNlf37MBST/NGMT0hwcu7yqFMt8JOOypjI+VeWDY6F2iFqLsKZY60ICDwx2gGHeuy5abKOYQbfD3yiF/7j2y[/tex]则，销钉安全。（5）杠杆系统的许可载荷为[tex=13.286x1.357]eKIEWbcxP2p+c8n1RC4DD1mX6pLsWOrcJPrpbMTNFBWlQSCCDmX3dlywwzQZqsZNAh/u2+1EevQ9PBkclPN6V4R1w5E98cPp/vaX2aFtwgWAQ0+bp7I2gu+QZ/NFioqW/xORDLT4oSXzB6DPMaFBvw==[/tex]

举一反三

内容

0
【计算题】5 ×8= 6×4= 7×7= 9×5= 2×3= 9 ×2= 8×9= 7×8= 5×5= 4×3= 5+8= 6 ×6= 3×7= 4×8= 9×3= 1 ×2= 9×9= 6×8= 8×0= 4×7=
1
输出九九乘法表。 1 2 3 4 5 6 7 8 9 --------------------------------------------------------------------- 1*1=1 2*1=2 2*2=4 3*1=3 3*2=6 3*3=9 4*1=4 4*2=8 4*3=12 4*4=16 5*1=5 5*2=10 5*3=15 5*4=20 5*5=25 6*1=6 6*2=12 6*3=18 6*4=24 6*5=30 6*6=36 7*1=7 7*2=14 7*3=21 7*4=28 7*5=35 7*6=42 7*7=49 8*1=8 8*2=16 8*3=24 8*4=32 8*5=40 8*6=48 8*7=56 8*8=64 9*1=9 9*2=18 9*3=27 9*4=36 9*5=45 9*6=54 9*7=63 9*8=72 9*9=81
2
输出九九乘法表。 1*1=1 2*1=2 2*2=4 3*1=3 3*2=6 3*3=9 4*1=4 4*2=8 4*3=12 4*4=16 5*1=5 5*2=10 5*3=15 5*4=20 5*5=25 6*1=6 6*2=12 6*3=18 6*4=24 6*5=30 6*6=36 7*1=7 7*2=14 7*3=21 7*4=28 7*5=35 7*6=42 7*7=49 8*1=8 8*2=16 8*3=24 8*4=32 8*5=40 8*6=48 8*7=56 8*8=64 9*1=9
3
下面是图的拓扑排序的是？(多选)[img=340x240]1802faef6ebcc2a.png[/img] A: 2 8 0 7 1 3 5 6 4 9 10 11 12 B: 2 8 7 0 6 9 11 12 10 1 3 5 4 C: 8 2 7 3 0 6 1 5 4 9 10 11 12 D: 8 2 7 0 6 9 10 11 12 1 3 5 4
4
下面语句的输出结果是？range(len('HelloWorld')) A: [1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11] B: 11 C: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10] D: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11]