AP_Phsics_B_-_Impulse_and_Momentum.ppt

Collisions in 2 dimensions Collisions in 2 dimensions AP Physics B Impulse and Momentum 消夹枣憨炮瞅咀含淡咆却睫癣战轨铡敞檀糟戈俩疏淄屠或诵爬贺赊属喧义AP_Physics_B_-_Impulse_and_MomentumAP_Physics_B_-_Impulse_and_Momentum Impulse = Momentum Consider Newton’s 2nd Law and the definition of acceleration Units of Impulse: Units of Momentum: Momentum is defined as “Inertia in Motion” Ns Kg x m/s 施匣姚溉澡队抛柿毁澳瓷骆协枪笨治郭初烫露使情峰饱捉却胀榷去骆鸣举AP_Physics_B_-_Impulse_and_MomentumAP_Physics_B_-_Impulse_and_Momentum Example A 100 g ball is dropped from a height of h = 2.00 m above the floor. It rebounds vertically to a height of h= 1.50 m after colliding with the floor. (a) Find the momentum of the ball immediately before it collides with the floor and immediately after it rebounds, (b) Determine the average force exerted by the floor on the ball. Assume that the time interval of the collision is 0.01 seconds. 相毁藐身店舔雁篇骋诲惕盆今哼板弯育中了拼遂朝捂亏寐竖瘦樱涤很狞掀AP_Physics_B_-_Impulse_and_MomentumAP_Physics_B_-_Impulse_and_Momentum Impulse is the Area Since J=Ft, Impulse is the AREA of a Force vs. Time graph. 炳醉挺受支摈伺字侣忿搽狈殆眶辐算班撮我飞耍渍躯界呸懂袭礁真侮岁沥AP_Physics_B_-_Impulse_and_MomentumAP_Physics_B_-_Impulse_and_Momentum How about a collision? Consider 2 objects speeding toward each other. When they collide...... Due to Newton’s 3rd Law the FORCE they exert on each other are EQUAL and OPPOSITE. The TIMES of impact are also equal. Therefore, the IMPULSES of the 2 objects colliding are also EQUAL 坷浴憾寅惰证兴僧擒接显择今孝纹析蛆腹擦每谐驻芳料弛筏刘侯捆是里烽AP_Physics_B_-_Impulse_and_MomentumAP_Physics_B_-_Impulse_and_Momentum How about a collision? If the Impulses are equal then the MOMENTUMS are also equal! 唉买鼓掣盯妥启衰揽辕搞箩似隐帅喳按爆炎轰涅由夺阂口专裕萍氰凤弄譬AP_Physics_B_-_Impulse_and_MomentumAP_Physics_B_-_Impulse_and_Momentum Momentum is conserved! The Law of Conservation of Momentum: “In the absence of an external force (gravity, friction), the total momentum before the collision is equal to the total momentum after the collision.” 抽泼艺割泊珊绚宁悼颧筹猖涉抹郎啡侩狡掉暑堪便考轮共顺孟案讨态杯淋AP_Physics_B_-_Impulse