1 . 如图为某游戏装置原理示意图。水平桌面上固定一半圆形竖直挡板,其半径为2R、内表面光滑,挡板的两端A、B在桌面边缘,B与半径为R的固定光滑圆弧轨道在同一竖直平面内,过C点的轨道半径与竖直方向的夹角为60°。小物块以某一水平初速度由A点切入挡板内侧,从B点飞出桌面后,在C点沿圆弧切线方向进入轨道
内侧,并恰好能到达轨道的最高点D。小物块与桌面之间的动摩擦因数为
,重力加速度大小为g,忽略空气阻力,小物块可视为质点。求:
(2)B和D两点的高度差;
(3)小物块在A点的初速度大小。
![](https://img.xkw.com/dksih/QBM/editorImg/2023/6/23/7fd268f4-a581-438c-9091-0f68cf214048.png?resizew=160)
A.m=0.7 kg,f=0.5 N | B.m=0.7 kg,f=1.0N |
C.m=0.8kg,f=0.5 N | D.m=0.8 kg,f=1.0N |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12acaf83b95c2e9230cf8cf39c77ec76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fda5655ef480683a2d3b74f0b523439.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7327dabea2692f22458498d7159ca83.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b72fd164e70ce98656095992bd150f9c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8fc87fceaca4f3df3918cf3734f5d7ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f9f699be1fbe9a7f8cc7c731ddc2b0ae.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f881cb9071ca8fea7cef4ab8d4865589.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11919c2d48fbf8eeff518ed621bbaa85.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c4ee1b7d06ac4c703e4c086b425c9c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f986badfc5dea707c164e2ab6c98dd06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb8485466d2127bd681a322f87c58f86.png)
(1)小滑块第一次到达D点时的速度大小;
(2)小滑块第一次与第二次通过C点的时间间隔;
(3)小滑块最终停止的位置距B点的距离。
A.弹簧的最大弹力为μmg |
B.物块克服摩擦力做的功为2μmgs |
C.弹簧的最大弹性势能为μmgs |
D.物块在A点的初速度为![]() |
A.![]() | B.![]() | C.![]() | D.![]() |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6b86c22b670a8e9f3896f9e8883fbbb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b15fa17c704f1988d059ba69a7ce304.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1eebd522c4de12f8255e649d3145d51.png)
A.物块的质量为![]() |
B.物块所受摩擦力![]() |
C.物块在最高点时重力势能为![]() |
D.物块上滑过程克服摩擦力做功为![]() |
(1)小物块的初速度v0及在B点时的速度大小;
(2)小物块滑至C点时,对圆弧轨道的压力大小;
(3)长木板至少为多长,才能保证小物块不滑出长木板。
![](https://img.xkw.com/dksih/QBM/2021/4/13/2698807184703488/2698852101144576/STEM/b3fd3b9f-61be-4b00-a2ac-fec4bd629e32.png?resizew=265)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4aa0df7f1e45f9de29e802c7f19a4f64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca66a268d6f46e0e9d5d9151b785be60.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e7f30167e1135806fe9de641870b1e6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3aa35a27cd912f997ca83658ff7dfc12.png)
(1)滑块第一次滑至圆形轨道最低点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(2)滑块与水平轨道间的动摩擦因数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1100379a4385b9ce064847bc21760adc.png)
(3)弹簧被锁定时具有的弹性势能。
9 . 如图所示,一个可视为质点、质量m=1kg的小物块,从平台上的A点以的初速度水平抛出,恰好无碰撞地从C点进入固定光滑圆弧轨道,最后小物块滑上紧靠轨道末端D点的质量M=2kg的长木板,并恰好能到达长木板的左端。已知长木板的上表面与圆弧轨道末端的切线相平,圆弧轨道的半径
,圆弧轨道对应的圆心角为θ,小物块与长木板间的动摩擦因数
,长木板与地面间的动摩擦因数
,不计空气阻力,取重力加速度大小
,sinθ=0.8。求:
(1)小物块滑上长木板时的速度大小;
(2)小物块与长木板间因摩擦产生的热量Q。
(1)整个运动过程中摩擦阻力所做的总功;
(2)动力车1匀速运动时的速度大小;
(3)因摩擦系统损失的动能和因碰撞系统损失的动能之比。
![](https://img.xkw.com/dksih/QBM/2022/2/13/2922631546249216/2923304023539712/STEM/e56e8950-9056-4f00-b5a1-da14dcc168ad.png?resizew=285)
![](https://img.xkw.com/dksih/QBM/2022/2/13/2922631546249216/2923304023539712/STEM/5b9c8b4a-035a-4944-b94a-c5d5465507d9.png?resizew=324)