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Answer 1

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Ôò${x}_{1}^{\;}={v}_{0}^{\;}{t}_{1}^{\;}+\frac{1}{2}a{t}_{1}^{2}$
´úÈëÊý¾Ý£º$2{t}_{1}^{\;}+\frac{1}{2}¡Á1{t}_{1}^{2}=160$
½âµÃ£º${t}_{1}^{\;}=16s$
´ËʱʯͷµÄËÙ¶ÈΪ${v}_{1}^{\;}={v}_{0}^{\;}+a{t}_{1}^{\;}=2+1¡Á16=18m/s$
Ôڴ˹ý³ÌÖУ¬ÓοÍÔ˶¯µÄλÒÆΪ${x}_{2}^{\;}=\frac{1}{2}{a}_{»¬}^{\;}£¨{t}_{1}^{\;}-1£©_{\;}^{2}$=$\frac{1}{2}¡Á0.4¡Á£¨16-1£©_{\;}^{2}$=45m
£¨2£©Ê¯Í·µ½Æµ×B´¦Ê±Óο͵ÄËÙ¶ÈΪ${v}_{2}^{\;}$=${a}_{ÓÎ}^{\;}$$£¨{t}_{1}^{\;}-1£©$=0.4¡Á£¨16-1£©=6m/s
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${v}_{¹²}^{\;}={v}_{1}^{\;}-{a}_{ʯ}^{\;}{t}_{2}^{\;}={v}_{m}^{\;}=6m/s$
¼´$18-2¡Á{t}_{2}^{\;}=6$
½âµÃ${t}_{2}^{\;}=6s$
ʯ¿éÔÚÕâ¶Îʱ¼äÄÚµÄλÒÆ${x}_{ʯ}^{\;}$=$\frac{{v}_{1}^{\;}+{v}_{¹²}^{\;}}{2}{t}_{2}^{\;}$=$\frac{18+6}{2}¡Á6=72m$
ÓοʹËʱµÄ×ÜλÒÆΪ${x}_{ÓÎ}^{\;}$=${x}_{2}^{\;}+{v}_{¹²}^{\;}{t}_{2}^{\;}$=45+6¡Á6=81m
ÓÉÓÚ${x}_{ʯ}^{\;}=72m£¼{x}_{ÓÎ}^{\;}=81m$
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