1、单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,速度和时间的关系,速度,-,时间图象,0,t/s,v/,m/s,2,8,4,3,1,2,5,4,6,S=,vt,从图中可获得那些信息?,物体运动状态。,任意时刻的速度。,可求位移,位移在数值上等于图象与坐标轴围成的面积。,0,t/s,v/,m/s,4,3,1,2,5,0,2,-2,4,6,-4,-6,-8,S=,vt,0,t/s,v/,m/s,20,50,20,15,5,10,25,30,40,时刻,t/s,速度,v/,(,m/s,),0,20,5,30,10,40,15,50,匀变速直线运动,在变速直线运
2、动中,如果在相等的时间内速度的改变相等,这种运动就叫做匀变速直线运动。,匀加速直线运动:速度随时间而均匀增加。,匀减速直线运动:速度随时间而均匀减小。,0,t/s,v/,m/s,2,8,4,3,1,2,5,4,6,0,t/s,v/,m/s,2,8,4,3,1,2,5,4,6,0,t/s,v/,m/s,2,8,4,3,1,2,5,4,6,0,t/s,x/m,2,8,4,6,4,3,1,2,5,根据图像分析物体的运动,并指出前,4,秒内物体的位移和第四秒末的速度。,0,t/s,x/m,4,3,1,2,5,1,5,2,3,4,0,t/s,v/,m/s,4,3,1,2,5,1,5,2,3,4,根据图像分析物体的运动,并指出前,4,秒内物体的位移和第四秒末物体的速度,及图像与纵轴交点的意义。,0,t/s,s/m,4,3,1,2,5,1,5,2,3,4,-1,0,t/s,v/,m/s,4,3,1,2,5,1,5,2,3,4,-1,根据图像分析物体的运动,并指出前,4,秒内物体的位移和第四秒末物体的速度,及图像与横轴交点的意义。,回到原点,调转方向,0,t/s,v/,m/s,4,0,t/s,s/m,4,2,1,5,2,3,4,1,