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1、物理八下知识点第七章 力1、力是物体对物体的作用，它不能离开物体 而单独存在，要产生力至少要有两个 物体，它们之间不一定 接触，其中一个是 施力物体，另一个是受力物体。物体间力的作用是 相互的，它们既是施力物体，同时也是受力物体。力可以产生 两种 作用效果：力可以改变物体的运动状态；力可以改变物体的形状 (或者说使物体发生形变 )。2、力的三要素是指：力的大小、方向和作用点。力一般用大写字母 F 来表示，在国际单位制中，力的单位是牛顿，简称 牛，其符号是 N。用一条带箭头 的线段把力的三要素 都表示出来的方法叫力的图示，力的示意图则只表示出 力的作用点和 力的方向。3、物体由于发生形变 而产生
2、的力叫弹力，常见的拉力、提力、压力、支持力 都属于弹力，弹力的方向总是垂直于受力面。测量力的工具是测力计，常用的测力计是弹簧测力计。弹簧测力计的工作原理是：在弹性限度内，弹簧受到的拉力越大，弹簧的伸长量就越长。相互作用的力总是大小相|精.|品.|可.|编.|辑.|学.|习.|资.|料.*|*|*|*|欢.|迎.|下.|载.第 1 页，共 12 页等、方向 相反、作用在同一 直线上，同时产生，同时消失，并且它们分别作用在两个物体上，这两个物体互为受力物体 和 施力物体。4、地面附近的物体由于地球 的吸引而受到的力叫重力，其作用点叫重心，施力物体是地球，用符号 G 表示，其方向总是 竖直向下，即与
3、水平面相垂直。质量分布均匀、形状规则的物体的重心在其几何中心，质量分布不均匀、形状不规则的物体的重心，可以采用悬挂法 来确定。重力的大小与物体的质量 成 正比，用公式表示是 G=mg,其中 G表示 重力，单位是 N，m 表示 质量，单位是 kg,g 表示 重力与质量的比，其值是 9.8N/kg，它表示的含义是：质量为 1kg 的物体受到的重力大小为9.8N。5、两个相互接触的物体要发生或已发生相对滑动时，在接触面间产生的阻碍物体相对运动的力，叫滑动摩擦力，方向 与物体相对运动的方向相反，理解时注意：滑动摩擦力的方向 与物体相对运动的方向相反，与物体的运动方向不一定相反，如人在行走时摩擦力与人行
4、走的方向相同，用传输带运送货物时摩擦力与物体运动的方向相同。滑动摩擦力作|精.|品.|可.|编.|辑.|学.|习.|资.|料.*|*|*|*|欢.|迎.|下.|载.第 2 页，共 12 页文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文
5、档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7
6、M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10
7、Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G
8、9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2
9、V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H
10、10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9用点在物体间的接触面上，一般把作用点画在物体的重心 上。滑动摩擦力的大小与压
11、力 的大小和 接触面的粗糙程度 有关，压力越大滑动摩擦力越大，接触面越粗糙滑动摩擦力越大。摩擦力共有三种：滑动摩擦力、滚动摩擦力、静摩擦力，在相同情况下，滚动摩擦力小于 滑动摩擦力。增大摩擦力的方法：增大压力、增大接触面的粗糙程度，减小摩擦力的方法：减小压力、减小接触面的粗糙程度、用滚动代替滑动、使接触面分离。第八章 力与运动1、一个力对物体的作用效果与几个力对物体的作用效果 相同，这个力就叫那几个力的合力，那几个力就叫这个力的 分力。已知分力 求 合力 叫力的合成。同一直线上的两个力F1、F2 的合力，如果F1、F2 方向相同，则F合=F1+F2，方向与 F1、F2 的方向相同；如果F1、F
12、2 方向相反，则 F 合=|F1-F2|，方向与 F1、F2 中较大力的方向相同，注意合力不一定比分力大。|精.|品.|可.|编.|辑.|学.|习.|资.|料.*|*|*|*|欢.|迎.|下.|载.第 3 页，共 12 页文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H
13、10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O
14、4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1
15、D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z
16、9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U
17、8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2
18、N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G92、牛顿第一定律：一切物体在没有受到外力作
19、用时，总保持 静止 或匀速直线运动状态，或者说总保持原来的运动状态，原来运动 的则会做匀速直线运动，原来 静止 的仍保持 静止。牛顿第一定律也说明力不是维持物体运动的原因，而是 改变物体运动状态的原因。牛顿第一定律也叫惯性定律。物体保持原来运动状态不变的性质叫惯性。惯性是一切物体所固有的一种属性，任何物体在任何时候、任何状态下都具有惯性。3、物体处于静止状态或 匀速直线运动状态称为 平衡状态。物体处于平衡状态时受到的几个力称为平衡力。二力平衡条件：二力作用在同一物体上，大小相等，方向相反，作用在同一直线上。物体处于平衡状态时，则它受平衡力作用，即所受合力为零，此时，物体处于静止状态 或 匀速直
20、线运动状态。4、物体在不受力或受平衡力作用时，将保持静止状态或 匀速直线运动状态；物体受非平衡力作用时，运动状态将会改变，包括物体由静到动，由动到静，由快到慢，由慢到快，速度方向发生改变。|精.|品.|可.|编.|辑.|学.|习.|资.|料.*|*|*|*|欢.|迎.|下.|载.第 4 页，共 12 页文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H
21、10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O
22、4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1
23、D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z
24、9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U
25、8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2
26、N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K
27、1Z9H10Y1 ZT4L1U8O4G9第九章 压强1、垂直作用在物体表面上的力叫压力，压力的作用效果与 压力的大小和受力面积大小有关，压力越大，受力面积 越小，压力的作用效果越明显。物体单位面积上受到压力叫 压强，计算公式：，其中 P 代表 压强，F 代表压力，S 表示 接触的受力面积。在国际单位制中，压力的单位是牛顿（N），面积的单位是平方米（m2），压强的单位是帕斯卡（Pa），1 Pa=1 N/m2。增大压力或减小受力面积，都可以增大压强，减小压力或增大受力面积，都可以减小压强。2、液体内部压强的规律：液体内部向各个方向都有压强；在 同一深度，液体内部向各个方向的压强相等；液体内部的压强
28、随深度的增加而增大；液体的压强与液体的密度有关，在不同液体的同一深度，密度越大压强越大。液体压强公式：P=gh，其中 P 表示 压强，单位是 Pa，表示 液体的密度，单位是 kg/m3，h 表示 液体的深度，单位是 m。规则容器底部液体的压强也可以用固体的压强计算公式进行计算。液体对容器底部的压力F 与容器所盛液体的重力G液的关系：上大下小容器FG 液。3、上端开口下部相连通的容器叫连通器，连通器原理是：连通器中的同种液体不流动时液面总保持相平，茶壶、船闸、锅炉水位计等都是连通器的应用。液体具有流动性，在受到外力作用时能把它受到的压强向各个方向传递。帕斯卡原理：密闭液体上的压强，能够大小不变地
29、向各个方向传递。汽车液压千斤顶、汽车液压刹车系统、水压机 都是液压技术的应用。4、大气对对浸在它里面的物体的压强叫大气压强，简称大气压，它产生的原因是：空气受重力并且有流动性。证明大气压存在的著名实验是马德堡半球实验，测出大气压强值的实验是 托里拆利实验，1 个标准大气压=760mm水银柱=10.3m水柱 =1.01 105 Pa。常用气压计：水银气压计、金属盒气压计。大气压强随海拔高度的增加而减小，液体的沸点随表面气压的增大而升高，随气压的减小而降低，这一性质的应用：高压锅。喝水、活塞式抽水机、医生用针筒抽药水都利用了大气压。|精.|品.|可.|编.|辑.|学.|习.|资.|料.*|*|*|
30、*|欢.|迎.|下.|载.第 6 页，共 12 页文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1
31、 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文
32、档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7
33、M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10
34、Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G
35、9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2
36、V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9第十章 流体的力现象1、把具有流动性 的液体和气体统称流体。伯努利原理：流体在 流速大的地方压强小，流体在 流速小的地方压强大。飞机升力产生的原因：空气对飞机机翼上下表面产生的压力差。飞机升力产生的过程：机翼形状上
37、下表面不对称(上凸)，使上方空气流速大，压强小，下方空气流速小，压强大，因此在机翼上下表面形成了压强差，从而形成压力差，这样就形成了升力。2、流体对浸入其中的物体的竖直向上的力叫 浮力，其方向是 竖直向上。浮力产生的原因：液体对浸在其中的物体的下上表面产生的压力差。浮力的大小与物体浸在液体中的体积及液体的密度有关，阿基米德原理：浸在液体中的物体受到浮力的大小等于物体排开的液体受到的重力。这一原理对气体也适用。3、浮力的计算方法及公式：称量法：F 浮=G-F；压力差法：F 浮=F 向上-F 向下；平衡法：F 浮=G 物=G 排=液 gV 排；公式法(根据：阿基米德原理)F 浮=G 排=液 gV
38、排，此法也适用于气体，F 浮=G 排=气gV 排。|精.|品.|可.|编.|辑.|学.|习.|资.|料.*|*|*|*|欢.|迎.|下.|载.第 7 页，共 12 页文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2
39、V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H
40、10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O
41、4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1
42、D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z
43、9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U
44、8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G94、浸在液体中的物体，其沉浮由它在液体中受到的浮力F浮与其重力G 物的大小关系决定。沉浮条件：当F
45、 浮G物时，物体上浮；当F 浮=G 物时，物体悬浮或漂浮；当 F 浮G 物时，物体下沉。实心物体的沉浮与物体、液体密度的关系：当物 液时，物体下沉。沉浮条件在实际生活中的应用：轮船、潜水艇、热气球。第十一章 功与机械1、如果 物体受力且 沿受力的方向移动了一定的距离，则这个力对物体做了功。做功的两个必要因素：有力作用在物体上；物体在力的方向上移动了距离。功的计算公式：W=FS，在国际单位制中，力的单位是N，距离的单位是m，功的单位是 N?m，它也叫焦耳，简称焦，其符号 J，1 J=1 N?m。力对物体没有做功的情况：物体受到了力的作用，但物体没有移动距离；物体虽然移动了距离，但物体没有受到力的
46、作用；物体移动了距离，也受到了力的作用，但力的方向与距离互相垂直。单位时间内做的功叫功率，其物理意义：它表示做功快慢的物理量。功率的计算公式是：，|精.|品.|可.|编.|辑.|学.|习.|资.|料.*|*|*|*|欢.|迎.|下.|载.第 8 页，共 12 页文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:
47、CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 H
48、C1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 Z
49、T4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编
50、码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6 HC1K1Z9H10Y1 ZT4L1U8O4G9文档编码:CY2N1D2V7M6