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> 一轻绳长为l，系着一质量为m的小球，在光滑水平面上做匀速圆周运动，小球运动的线速度为v，求：（1）小球运动的周期；（2）在小球运动半圈的时间内重力对小球冲量的大小；（3）在小球运动半圈的时间内绳的拉力对小球冲量的大小．

问题：

发布时间：2024-09-10

一轻绳长为l，系着一质量为m的小球，在光滑水平面上做匀速圆周运动，小球运动的线速度为v，求：
（1）小球运动的周期；
（2）在小球运动半圈的时间内重力对小球冲量的大小；
（3）在小球运动半圈的时间内绳的拉力对小球冲量的大小．

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