如图所示，重为2.45牛的木块，用细线悬着浸没在装有水的柱形容器中，细线对木块的拉力为1.2牛，细线断后木块露出水面前，浮力和重力的合力为　_1牛．当木块静止时，浮力与重力之比为_2　；木块在露出水面_刷题宝

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如图所示，重为2.45牛的木块，用细线悬着浸没在装有水的柱形容器中，细线对木块的拉力为1.2牛，细线断后木块露出水面前，浮力和重力的合力为　____ 牛．当木块静止时，浮力与重力之比为____ 　；木块在露出水面之前与之后、下上表面所受水的压强差____ （选填“变大”、“不变”或“变小”）．

上一题下一题 0.0难度选择题更新时间:2013-01-17 03:04:37

答案(点此获取答案解析）

1.2,1：1,变小

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