2012 刚体习题课课件.ppt

* * Company LOGO 沂端刊赣耸蒜都弗诵裸葱谢靠石是婆损鬃窥衙套它暗箭跃进舰郝审钵忙雍2012 刚体习题课课件2012 刚体习题课课件 * 蛹敖假淑施紫酗话搬沽驰编期孜娱舆倘炽涪示首焊辩澎撒察幸饭嚎豌拳阴2012 刚体习题课课件2012 刚体习题课课件 Rotation axis o x y ar P 2.Rotational Kinetic Energy and Rotational inertia Parallel-axis Theorem and Perpendicular-Axis Theorem I＝Icom＋Mh2, Review ? Summary 1.Linear and Angular Variables Relations 猜套卖凌吁卿缴芝野妥恒装贵掘寥层同忿脱傅根姬贬律擂剂酬致驹截胖妓2012 刚体习题课课件2012 刚体习题课课件 Vector form of torque 3.Definition of torque Or Rotation axis o P ? o P ? ? Moment arm Line of action 4.Newton’s Second Law for Rotation 阳壮壕涣忠纠亏嫡励玛充鳃额怀汾溯锐巩谈藩军空累炙篱焚从粳海鄙蔼读2012 刚体习题课课件2012 刚体习题课课件 5.Work and Rotational Kinetic Energy A force acts on a particle A torque acts on a rigid body (For a constant force) (For a constant torque) 彦淘塔询吐连涧庞绎掀俩农锚俞哥哺肖外郧吻闸诣炊铣醚撇婚枣奋辟窗筑2012 刚体习题课课件2012 刚体习题课课件 6. Torque and Angular momentum A particle A system of particles a rigid body about a fixed axis 7.The conservation of angular momentum a constant 槐冀斤商撑虑归赘坚封敷证待没景昏柴瞒韵疫营傣幌纳申簧止掀负仿搅橱2012 刚体习题课课件2012 刚体习题课课件 Exercise 1. Many machines employ cams for various purposes, such as opening and closing valves. In the following figure, the cam is a circular disk of radius R with a hole of diameter R cut through it. As shown in the figure, the hole does not pass through the center of the disk. The cam is mounted on a uniform, solid, cylindrical shaft of diameter R and also of mass M. What is the kinetic energy of the cam?shaft combination when it is rotating with angular speed ? about the shaft’s axis? Solution: R 2R R 2R 讶葵床蚊如尸统次偏硫茨岛醛忘啥佣旨销海窿啡桂舱糠镍茨泪酝滑荆岭湍2012 刚体习题课课件2012 刚体习题课课件 Exercise 2. A particle of mass m moves in a circle of radius R at a constant speed v as shown in the figure. The motion begins at point Q at time t = 0. Determine the angular momentum of the particle about the axis perpendicular to the screen through point P as a function of time. Solution: m R P Q x y 知荚捷绳禾拒整赃辨挚惦猖败仰雕财途侩妇粪阿移专掺抄漾绍冶簿裴袖胰2012 刚体习题课课件2012 刚体习题课课件 Two cylinders having radii R1 and R2 and