题干

如图所示用斜面、木板、棉布、玻璃板、小车做“探究阻力对物体运动的影响”的实验.

①为了使小车到达水平面的速度相同,应让小车从斜面的____自由下落.

②小车在水平玻璃板上运动时受到____个力的作用.

③通过实验观察到:小车受到的阻力越小,运动的路程越大;由此可以推测,如果小车在绝对光滑的水平面上运动,即不受阻力作用,小车将做____运动.该结论____(能/不能)通过实验验证,因为____

上一题 下一题 0.0难度 选择题 更新时间:2014-11-26 02:19:00

答案(点此获取答案解析)

同一高度,三,匀速直线,不能,不可能有绝对光滑的水平面

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