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杠杆是历届初中应用物理知识竞赛重点考察的知识点之一,由于这一知识在生产和生活中的应用十分广泛,因此,每年用形式各异的应用题目来检测学生对这一知识掌握的灵活程度.例1下图a是一个指甲刀.(1)这个指甲刀是由哪几个杠杆组成的?它们的支点各在哪里?(2)小明的指甲刀有图a和图b两种组装方式.请分析哪种组装方式更合理.解析:(1)AC可绕C点转动,DE可绕E点转动,GE可绕E点转动,故AC、DE和GE是三个杠杆,它们的支点分别是C、E、E(2)对于杠杆DE来说,指甲在D点对它的作用力是阻力;AC在
Leverage is one of the most important points in the junior high school applied physics knowledge competition. Because this knowledge is widely used in production and life, it uses different forms of application topics each year to detect students’ agility in this knowledge. Degree. Example 1 The following figure a is a nail clipper. (1) Which are the levers of the nail clipper? Where are their fulcrums? (2) Xiao Ming’s nail clippers are shown in Figure A and Figure b. Method. Please analyze which assembly method is more reasonable. Analysis: (1) AC can rotate around point C, DE can rotate around point E, GE can rotate around point E, so AC, DE and GE are three levers, their The fulcrums are C, E, and E(2). For leverage DE, the force applied to the fingernail at D is resistance; AC