试题与答案

如甲图所示,小车上固定着硬质支架,杆的端点固定着一个质量为m的小球.杆对小球的作

题型:选择题

题目:

如甲图所示,小车上固定着硬质支架,杆的端点固定着一个质量为m的小球.杆对小球的作用力的变化如乙图所示,则关于小车的运动,下列说法中正确的是(杆对小球的作用力由F1变化至F4)(  )

A.小车向右做匀加速运动

B.小车由静止开始向右做变加速运动

C.小车的加速度越来越大

D.小车的加速度越来越小

答案:

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参考答案:C,D解析: 1989年11月5日至7日,澳大利亚首倡发起,澳大利亚、美国、加拿大、日本、韩国、新西兰和东盟6国在堪培拉举行亚太经济合作会议首届部长级会议,这标志着亚太经济合作会议的成立。1991年11月...

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