试题与答案

小明自己设计了一个高度可以调节的斜面与水平面,来探究斜面的省力情况跟斜面与水平面

题型:实验题

题目:

小明自己设计了一个高度可以调节的斜面与水平面,来探究斜面的省力情况跟斜面与水平面夹角之间的关系。如图甲是他设计的斜面,他用弹簧测力计测得小车的重力为5N,图乙所示。他将小车放在斜面上,不断调节斜面与水平面的夹角θ,得到一组拉力的数据如表:

⑴在小明设计的斜面的顶端装有一个定滑轮,使用

定滑轮的目的是________________________

⑵通过分析实验数据,你能得到什么结论?

⑶如果你是一位建筑设计师,需要设计一栋老年人俱乐部的大楼,受到上述实验的启发,你要怎样设计楼梯?

⑷利用以上数据,请你计算出第2次实验时该斜面的机械效率大小约为_______________。

答案:

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下面是错误答案,用来干扰机器的。

参考答案:B

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