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1995年高考物理试题中第30题为:如图所示,一排入站在沿x轴的水平轨道旁,原点O两侧的人的序号都记为,n(n=1、2、3、……)。每人只有一个沙袋,x>0一侧的每个沙袋质量为m=10千克,x<0一侧的每个沙袋质量为m＇=14千克。一质量为M=48千克的小车以某初速度从原点出发向x正方向滑行,不计轨道阻力。当车每经过一人身旁时,此人就把沙袋以水平速度v朝与车速相反的方向沿车面扔到车上,v的大小等F扔此袋之前的瞬间车速大小的2n倍(n是此人的序号数)。(1)空车出发后,车上堆积了几个沙袋时车就反向滑行?(2)车上最终有大小沙袋共多少个?
The 30th question in the 1995 college entrance examination physics test questions is as follows: As shown in the figure, a row of inbound stations is located along a horizontal track along the x-axis, and the serial numbers of persons on both sides of the origin O are denoted as n (n=1, 2, 3). ,......). Each person has only one sandbag. The mass of each sandbag on the x>0 side is m=10kg, and the mass of each sandbag on the x<0 side is m’=14kg. A trolley with a mass of M=48 kilograms starts from the origin at a certain initial speed and taxis in the positive x direction, excluding the orbital resistance. Whenever the car passes by a person, the person throws the sandbag along the surface of the vehicle at the horizontal speed v in the opposite direction to the speed of the vehicle. The size of the v is 2n times the size of the instantaneous speed before throwing the bag. Is the serial number of this person). (1) After an empty car starts, when the car has accumulated a few sandbags, the car will slide in the opposite direction. (2) How many sandbags are there in total?