《杠杆画力臂和杠杆平衡条件特好.ppt

F1 F2 L1 L2 O 画出各力和力臂 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. O F2 F1 L1 L2 画出下图杠杆的支点、动力、阻力、动力臂、阻力臂 O F2 F1 阻力和动力的方向和支点的关系 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 画出下图杠杆的支点、动力、阻力、动力臂、阻力臂 F1 F2 L1 L2 O F1 F2 L1 L2 O Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 如图所示的杠杆中，动力的力臂用L表示，图中所画力臂正确的是（ ） D Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 完成活动学习卡P2的练习 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 图中，杠杆有可能平衡的是（ ） D 在图6中，O为支点，力臂最长的力是 （ ） 　　A．F1 　　B．F2　 　　C．F3　　 D．F4 C Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 起钉子 玩跷跷板 撬石头 硬棒在工作时有什么共同特点？ Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 什么是杠杆？ 一、杠杆 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 这些都应用了杠杆原理 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 认识杠杆 用剪刀剪断电线 思考以下几个问题： 1、这些工具的材质在软硬程度上有什么共同特点？ 2、在工作中它们发生了怎样的运动? 3、在什么条件下它们才能这样运动? 用镊子夹取铁钉 用起子开起汽水瓶 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 提问：杠杆有什么共同的特征呢？ 1 . 2 . 3. 固定点 绕固定点转动 硬棒 归纳结论 1. 杠杆：在力的作用下，能绕某一固定点转动的硬棒，物理学中叫杠杆。 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 远古 现代 复杂 简单 远古的撬棒 古代的杆秤 太空机械臂 道钉撬 Evaluation only. Create