[理学]chapter 5 momentum.pptVIP

1.(Example 9-16) A rocket is shot into the air as shown. At the moment it reaches its highest point, a horizontal distance d from its starting point, a prearranged explosion separates it into two parts of equal mass. Part I is stopped in midair by the explosion and falls vertically to Earth. Where does part II land? C O m 2m m x d d Solution: C O m 2m m x d d 2. A boat of mass 200kg with length 4m is still in water. A man of mass 50kg is standing at one end of the boat. How long will the boat move when the man walk from one end to the other. Solution: Take the man and boat as a system and the net force is zero in horizontal direction. At the beginning x O So Final position x O 3 (Example 9-10) Ballistic Pendulum . The projectile, of mass m, is fired into a large block of mass M, which is suspended like a pendulum.( Mm). Determine the relation between the initial horizontal speed of the projectile, v, and the height h. Solution: Momentum is conserved Conservation of mechanical energy Combine the two equations * collision collide impulse momentum linear momentum impulsive force elastic collision inelastic collision completely inelastic collision isolated system center of mass law of conservation of momentum symmetrically Key word and Terms 碰撞 冲量 动量 线动量 冲力 弹性碰撞 非弹性碰撞 完全非弹性碰撞 孤立系统 质心 动量守恒定律 对称地 5.1 linear momentum and impulse 9-1,3 Chapter 5 Conservation of linear momentum and collisions chap.9 5.2 The law of conservation of linear momentum 9-2 5.3 Collisions 9-3~7 Homework：9-2, 5, 41, 86, 105 5.4 Center of Mass and translational motion 9-8,9 The effect of force over a time interval The effect of force over some distance Work ，kinetic energy, potential energy Work-energy principle Principle of conservation of mechanical energy Momentum ， Impulse ， momentum theorem Law of conservation of linear momentum 5.1 linear momentum and impulse 9-1,3 1. linear momentu