一物体从斜面顶端由静止开始匀加速下滑，经过斜面中点时速度为2m/s，则物体到达斜面底端时的速度为（ 一物体从斜面顶端由静止开始匀加速下滑，他到达底端的速度是,则...
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\u5047\u8bbe\u5230\u5e95\u7aef\u901f\u5ea6\u4e3aV\uff0c\u659c\u9762\u9ad8H
\u7531\u80fd\u91cf\u8f6c\u6362\u53ef\u77e5mgH=mV^2/2-----(1)(^\u662f\u4e58\u65b9\u7b26\u53f7\uff0c\u5e94\u8be5\u61c2\u54e6\uff1f\uff09
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\u7531\u80fd\u91cf\u5b88\u8861 mgH=mgH/2+mv^2/2-----(2)
\u4e24\u5f0f\u8054\u7acb\uff0cv=1.414V/2(1.414\u662f2\u5f00\u6839\u53f7\uff0c\u6211\u6839\u53f7\u6253\u4e0d\u51fa\u6765\uff0e\uff0e\uff0e\uff09
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v12＝2a?
| x |
| 2 |
v22＝2ax
联立两式解得：v2＝
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