追及问题是高中物理非常常见的一类题,是难点,也是考试的热点,它是以生活中物理现象为依据,所涉及的物理知识包括运动和力、功和能等,所以要解决这类题型需要较深的物理功底,能比较全面的考查知识和思维能力.“追及”的主要条件是两个物体在追赶过程中处于同一位置,常见的情形有三种:一是初速度为零的匀加速运动的物体甲追同方向的匀速运动的物体乙,一定能追上,在追上之前两物体有最大距离的条件是两物体速度相等,即v甲=v乙;二是匀速运动的物体甲追赶同方向做匀加速运动的物体乙,存在一个恰好追上或者恰好追不上的临界条件是两物体速度相等,即v甲=v乙,此临界条件启发我们一个判断此种追赶情形能否追上的方法,即通过比较两物体处在同一位置时的速度大小来分 It is a difficult point and a hot spot for examinations to catch up with the problems in high school physics. It is based on the physical phenomena in life. The physical knowledge involved includes movement and strength, work and energy, and so on, so to solve this problem Questions require deeper physical skills, can more comprehensive examination of knowledge and thinking ability. “Chase and” the main condition is that two objects in the catch-up process in the same position, there are three common situations: First, the initial speed of Zero uniform acceleration of the object A chase with the direction of the uniform motion of the object B, will be able to catch up, before overtaking the two objects have the maximum distance condition is equal to the speed of the two objects, namely v A = v B; second uniform speed A moving object to catch up with the same direction to do uniform acceleration of the object B, there is a catch up, or just catch up with the critical condition is equal to the velocity of the two objects, namely v A = v B, this critical condition inspired us to judge this Catch-up situation can catch up with the method, that is, by comparing the two objects in the same position when the speed of the points