光滑斜面的长度为L，一物体自斜面顶端由静止开始匀加速滑至底端，经历的时间为t，则不正确的是：（ ） 光滑斜面的长度为L,一物体自斜面顶端由静止开始匀加速滑至底端...

\u5149\u6ed1\u659c\u9762\u7684\u957f\u5ea6\u4e3aL\uff0c\u4e00\u7269\u4f53\u81ea\u659c\u9762\u9876\u7aef\u7531\u9759\u6b62\u5f00\u59cb\u5300\u52a0\u901f\u6ed1\u81f3\u5e95\u7aef,\u7ecf\u5386\u7684\u65f6\u95f4\u4e3at\uff0c\u5219\u4e0b\u5217\u8bf4\u6cd5\u6b63\u786e\u7684\u662f\uff08

ACD \u8bd5\u9898\u5206\u6790\uff1a\u5e73\u5747\u901f\u5ea6\u7b49\u4e8e\u603b\u4f4d\u79fb\u6bd4\u603b\u65f6\u95f4\uff0c\u6240\u4ee5\u7269\u4f53\u8fd0\u52a8\u5168\u8fc7\u7a0b\u4e2d\u7684\u5e73\u5747\u901f\u5ea6\u662fL/t,A\u6b63\u786e\uff0c\u67d0\u6bb5\u5e73\u5747\u901f\u5ea6\u7b49\u4e8e\u4e2d\u95f4\u65f6\u523b\u7684\u77ac\u65f6\u901f\u5ea6\uff0c\u6240\u4ee5\u7269\u4f53\u5728t/2\u65f6\u7684\u77ac\u65f6\u901f\u5ea6\u662fL/t\uff0cB\u9519\uff0c\u6ed1\u5230\u5e95\u7aef\u65f6\u7684\u901f\u5ea6\u662f2\u500d\u7684\u5e73\u5747\u901f\u5ea6\u53732L/t\uff0c \uff0c\u5219\u4e2d\u70b9\u7684\u77ac\u65f6\u901f\u5ea6\u662f L/t\uff0cC\u5bf9\uff0cv=at\uff0c\u77ac\u65f6\u901f\u5ea6\u4e0e\u65f6\u95f4\u6210\u6b63\u6bd4\uff0c\u4e2d\u70b9\u901f\u5ea6\u4e0e\u5e95\u7aef\u901f\u5ea6\u4e4b\u6bd4\uff1a \u6240\u4ee5\u7269\u4f53\u4ece\u9876\u70b9\u8fd0\u52a8\u5230\u659c\u9762\u4e2d\u70b9\u6240\u9700\u7684\u65f6\u95f4\u662f t/2\uff0cD\u5bf9\u70b9\u8bc4\uff1a\u7269\u4f53\u7684\u5e73\u5747\u901f\u5ea6\u7b49\u4e8e\u4f4d\u79fb\u4e0e\u65f6\u95f4\u4e4b\u6bd4\uff0e\u7269\u4f53\u505a\u5300\u52a0\u901f\u76f4\u7ebf\u8fd0\u52a8\uff0ct\u65f6\u95f4\u5185\u5e73\u5747\u901f\u5ea6\u7b49\u4e8e\u4e2d\u70b9\u65f6\u523b\u7684\u77ac\u65f6\u901f\u5ea6\uff0e\u7531\u659c\u9762\u7684\u957f\u5ea6L\u548c\u65f6\u95f4t\uff0c\u6c42\u51fa\u52a0\u901f\u5ea6\uff0c\u7531\u4f4d\u79fb\u901f\u5ea6\u516c\u5f0f\u6c42\u51fa\u659c\u9762\u4e2d\u70b9\u7684\u77ac\u65f6\u901f\u5ea6\uff0c\u518d\u7531\u901f\u5ea6\u516c\u5f0f\u6c42\u89e3\u7269\u4f53\u4ece\u9876\u7aef\u8fd0\u52a8\u5230\u659c\u9762\u4e2d\u70b9\u6240\u9700\u7684\u65f6\u95f4

(1)\u9519\uff0c\u5e73\u5747\u901f\u5ea6=\u4e2d\u95f4\u65f6\u523b\u77ac\u65f6\u901f\u5ea6=L/2t
\uff082\uff09\u5bf9\uff0c\u8fd9\u4e2a\u4e0d\u7528\u89e3\u91ca\u4e86\u5427
\uff083\uff09\u5bf9\uff0c\u753b\u56fe\uff0c\u76f8\u4f3c\u4e09\u89d2\u5f62\u5f97\u4f4d\u79fb\u6bd4\u4e3a1:2\uff0c\u6b64\u65f6\u65f6\u95f4\u4e0e\u4e2d\u70b9\u65f6\u523b\u6bd4\u4e3a1\uff1a\uff08\u6839\u53f72\uff09/2\uff0c\u659c\u9762\u4e2d\u70b9\u77ac\u65f6\u901f\u5ea6=\uff08L/t\uff09*[1/(\u6839\u53f72/2\uff09] \uff0c\u89e3\u5f97\u221a2L/t
\uff084\uff09\u5bf9\uff0c\u4e0a\u9898\u89e3\u6cd5\uff0c\u53ef\u5f97

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