试题与答案

小刚和小明在探究滑轮组的机械效率与哪些因素有关的实验中,使用几个规格相同的滑轮分

题型:问答题

题目:

小刚和小明在探究滑轮组的机械效率与哪些因素有关的实验中,使用几个规格相同的滑轮分别组成“一定一动”滑轮组和“两定两动”滑轮组做实验,记录的实验数据如下表.假设实验中滑轮轴的摩擦、绳重均忽略不计.请根据表格中的实验数据回答下列问题:

项目

滑轮组

钩码重/N钩码上升高度/m绳端拉力/N绳端上移的距离/m机械效率
一定一动滑轮组40.11.60.383.3%
60.12.20.390.9%
80.12.90.392.0%
两定两动滑轮组40.11.10.572.7%
60.11.40.5
80.11.80.588.9%
(1)请将表中数据补充完整.

(2)分析比较表中的数据,可以初步得到滑轮组机械效率与所提升的物体所受重力之间的定性关系是:使用同一滑轮组提升重物,滑轮组的机械效率随提升物体所受重力的增加而增大.除此之外,根据表中的实验数据你还可以得到的初步结论是:______.

答案:

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