弹力重力摩擦力考点解析.doc

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FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 DIV.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 P.MsoHeaderBORDER-RIGHT: medium none; PADDING-RIGHT: 0cm; BORDER-TOP: medium none; PADDING-LEFT: 0cm; FONT-SIZE: 9pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: medium none; LAYOUT-GRID-MODE: char; PADDING-TOP: 0cm; BORDER-BOTTOM: medium none; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: centerDIV.MyFav_1321582532770 LI.MsoHeaderBORDER-RIGHT: medium none; PADDING-RIGHT: 0cm; BORDER-TOP: medium none; 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FONT-SIZE: 9pt; TEXT-INDENT: 9pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 DIV.MsoBodyTextIndent3TEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 9pt; TEXT-INDENT: 9pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 P.MsoPlainTextTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoPlainTextTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; TEXT-ALIGN: justifyDIV.MyFav_1321582532770 DIV.MsoPlainTextTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; TEXT-ALIGN: justifyDIV.MyFav_1321582532770 DIV.Section1page: Section1“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽考点一、弹力、弹簧测力计“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽物体能恢复到原来的形状和体积的性质，叫做弹性。物体由于弹性形变而产生的力叫做弹力。弹簧测力计的原理是：在弹性限度内弹簧受到的拉力越大，弹簧的伸长就越长。使用弹簧测力计应注意：（1）观察弹簧测力计的量程及分度值，加在弹簧测力计上的力不能超过其量程。（2）使用前将测力计的指针调到零。使用时力的方向与弹簧的轴线一致。（3）读数时，视线应与刻度板面垂直。“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽例1我们之所以能用弹簧制作测力计，是因为在弹簧的弹性限度内（ ）“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽A弹簧受到的拉力跟弹簧的长度成正比“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽B弹簧受到的拉力跟弹簧的伸长成正比“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽C弹簧的长度跟所受拉力成正比“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽D弹簧的伸长跟所受拉力成正比“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽解析：弹簧是弹簧测力计的主要部件，它的基本原理是：弹簧受到拉力作用时会发生弹性形变，拉力越大，形变也越大，即弹簧所受拉力越大，弹簧的伸长也越长。通过进一步实验研究，可知弹簧的伸长与拉力成正比。“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽叙述弹簧测力计原理时，不能把因果关系颠倒：拉力是弹簧发生形变的原因，而弹簧的伸长是拉力作用的结果；而在实际使用弹簧测力计时，我们却是根据弹簧的形变（伸长了多少）来度量拉力大小的。“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽答案：D“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽例2如图左所示，弹簧测力计的一端受到4N的拉力作用，另一端也受到4N的拉力作用，则该弹簧测力计的示数是（ ）“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽A0 B2N C4N D8N“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽解析： 有的同学认为弹簧测力计的两端都受到拉力的作用，因此弹簧测力计的示数应是这两个力的和，即8N，因此认为选项正确。“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽我们可以转换思路来考虑，假如我们把弹簧测力计的一端固定（如图右），在其挂钩上施加N的拉力。这时墙面受到弹簧测力计向左的拉力为4N，根据物体间力的作用是相互的，相互作用力大小相等。墙对弹簧测力计也有一个向右的拉力，为4N。弹簧测力计的示数大小取决于弹簧测力计挂钩上所受的力。不是吊环与挂钩上的力简单相加。“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽答案：C“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽考点二、重力“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽重力是由于地球对物体的吸引而产生的。重力的大小可由弹簧测力计测量。实验表明重力的大小与物体的质量成正比，公式G = mg。物体受到重力的方向都是竖直向下的，利用这一特点，不仅能检查墙壁是否竖直，而且能检查桌面或窗台是否水平。重力在物体上的作用点叫重心。“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽例3足球运动员把足球踢向空中，若不计空气阻力。下图是表示足球在空中飞行的受力图，正确的是（G表示重力，F表示脚对球的作用力）（ ）“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽解析：重力是地球表面附近的物体由于地球的吸引而使物体受到的力。足球运动员把足球踢向空中时，若不考虑空气的阻力，则足球只受重力的作用，而重力的方向总是竖直向下的。观察四个选项，空中只受重力的受力图，只有选项B正确。“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽答案：B“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽例4我国“嫦娥工程”预计在2019年实施落月探测。已知月球上无大气、无磁场，物体在月球上所受重力只相当于地球上的1/6。在月球上，你认为下列情况可能的是（ ）“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽A利用降落伞降落，以确保安全落月 B用指南针确定方向“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽C听到月球车行驶发出的声音 D轻易地将60kg的物体举起“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽解析：月球上是真空，降落伞不起作用，A错；月球上没有磁场，故用指南针不能确定方向，B错；月球上没有空气，真空不能传声，C错；质量为60kg的物体，在月球上仅“重”100N，人能轻易将其举起，D正确。“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽答案：D“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽考点三、增大或减小摩擦力的方法“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽增大摩擦力的方法有：增大压力、使接触面变粗糙、变滚动为滑动。“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽减小摩擦力的方法有：减小压力、使接触面变光滑、变滑动为滚动（滚动轴承）、使接触面彼此分开（加润滑油、气垫、磁悬浮）。“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽例5如下图所示的四个实例中，目的是为了减小摩擦的是“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽解析：浴室脚垫做得凹凸不平、防滑地砖表面做得较粗糙、旅游鞋底有凹凸的花纹都是为了增大接触面的粗糙程度来增大摩擦；轮滑鞋装有滑轮是变滑动为滚动，目的是为了减小摩擦。“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582532770 P.MsoNormalTEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman" TEXT-ALIGN: justifyDIV.MyFav_1321582532770 LI.MsoNormalTEXT-JUSTIFY: inter-ideograph; 锹塔抛脏先遇矢谍赔司俘遮搐悟搭铺驶絮瞻甘蒋胞伎盗智资朋觅哩友啸汽胰古练蹦鹿证作浑尤遭血躁系埋汇燃钎呆崇凿扣坠允忍熄惹凋电奶堑伪抽答案：B“弹力、重力、摩擦力”考点解析第 页“弹力、重力、摩擦力”考点解析 DIV.MyFav_1321582