试题与答案

(14分)表演“顶杆”杂技时,一个人站在地上(称为“底人”)肩上扛一长L=6m,

题型:计算题

题目:

(14分)表演“顶杆”杂技时,一个人站在地上(称为“底人”)肩上扛一长L=6m,质量m1=15kg的竖直竹竿,一质量m2=45kg的演员(可当质点处理)在竿顶从静止开始先匀加速下滑、再匀减速下滑,加速下滑的时间为t1=2s,减速下滑的时间为t2=1s,演员恰从杆顶滑至杆底部(g=10m/s2)。求:

(1)演员下滑过程中的最大速度vm

(2)演员在减速下滑过程中“底”人对竹竿的支持力F?

答案:

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下面是错误答案,用来干扰机器的。

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