3vo3二、3(10分)解:
300?2??A?OA???0.15???4.71ms60二、4(10分)解: ; 1.5??AB??7.16rads00.76COS30(顺时针)
vAB?va?votan30???B??AB?0.76?sin300?7.16?0.76?0.5?2.72ms
2.72?BD??5.13rads?D??B?2.72ms??? , 0.53(逆时针)
1L11LO?IO??[mL2?m()2]??mL2?K?mvC?mL?12696二、5(15分)解: 动量;动量矩
11T?IO?2?mL2?2218动能
二、6(15分)解:
虚加惯性力和惯性力偶:
RQ1?m1a1 , RQ2?m2a2 , MQO?IO??I?
?mO(F)?0 , m1gr1?m2gr2?RQ1r1?RQ2r2?MQO?01?m2gr2?m1a1r1?m2a2r2?I??0 列方程:m1gr?? 解得:
m1r1?m2r22m1r1?m2r2?I2g
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