Question

3£®ÁÔ±ªÊÇÔÚ½µØÉϱ¼ÅÜËÙ¶È×î¿ìµÄ¶¯Îµ«ÓÉÓÚÉíÌåÒòËØ£¬Æä¸ßËÙ±¼Åܲ»ÄÜά³Ö½Ï³¤Ê±¼ä£¬·ñÔò½«»áÉíÌå¹ýÈȶøΣ¼°ÉúÃü£®Ò»Ö»ÁÔ±ªÔÚij´Î×·»÷ÁÔÎïʱ£¬ÏÈ×öÔȼÓËÙÖ±ÏßÔ˶¯£¬¾­¹ýt₁=4sµÄʱ¼ä£¬ÆäËÙ¶ÈÓɾ²Ö¹´ïµ½×î´ó£¬È»ºóÔÈËÙÔ˶¯t₂=6sµÄʱ¼äÈÔȻûÓÐ×·ÉÏÁÔÎΪÁ˱£»¤×Ô¼º£¬Ëü·ÅÆúÁËÕâ´Î×·²¶£¬²¢ÒÔ´óСa=3m/s²µÄºã¶¨¼ÓËٶȼõËÙ£¬¾­¹ýt₃=10sµÄʱ¼äͣϣ®½«ÁÔ±ªµÄ×·²¶¹ý³ÌÊÓΪ×öÖ±ÏßÔ˶¯£®Çó£º
£¨1£©ÁÔ±ªÔÚ±¼Åܹý³ÌµÄ×î´óËÙ¶Èv_max£»
£¨2£©ÁÔ±ªÔÚÕû¸ö¹ý³ÌÖÐÔ˶¯µÄ¾àÀëx£®

Answer 1

·ÖÎö £¨1£©¸ù¾ÝÔȱäËÙÖ±ÏßÔ˶¯µÄËÙ¶Èʱ¼ä¹«Ê½Çó³öÁÔ±ª±¼ÅܵÄ×î´óËٶȣ¬
£¨2£©¸ù¾ÝλÒƹ«Ê½Çó³ö¸÷¸öÔ˶¯¹ý³ÌµÄλÒÆ£¬¼´¿ÉÇó³ö×ÜλÒÆ

½â´ð ½â£º£¨1£©ÓÉÌâ¿ÉÖª£¬ÁÔ±ª¿ªÊ¼¼õËÙʱµÄËٶȼ´ÎªÆä±¼Åܹý³ÌµÄ×î´óËٶȣ¬ÓУº$a=|\frac{0-{v}_{max}^{\;}}{{t}_{3}^{\;}}|$
´úÈëÊý¾Ý£º$3=\frac{{v}_{max}^{\;}}{10}$
½âµÃ£º${v}_{max}^{\;}=30m/s$
£¨2£©ÁÔ±ªÓɾ²Ö¹¼ÓËÙµ½×î´óËٶȵĹý³ÌÖÐÔ˶¯µÄ¾àÀëΪ£º
${x}_{1}^{\;}=\frac{{v}_{max}^{\;}}{2}•{t}_{1}^{\;}=\frac{30}{2}¡Á4=60m$
ÁÔ±ªÔÈËÙÔ˶¯µÄ¾àÀëΪ£º${x}_{2}^{\;}={v}_{max}^{\;}{t}_{2}^{\;}=30¡Á6=180m$
ÁÔ±ª¼õËÙÔ˶¯µÄ¾àÀëΪ£º${x}_{3}^{\;}=\frac{{v}_{max}^{\;}}{2}•{t}_{3}^{\;}=\\;\frac{30}{2}¡Á10=150m$$\frac{30}{2}¡Á10=150m$
ÓÖ$x={x}_{1}^{\;}+{x}_{2}^{\;}+{x}_{3}^{\;}=60+180+150=390m$
´ð£º£¨1£©ÁÔ±ªÔÚ±¼Åܹý³ÌµÄ×î´óËÙ¶È${v}_{max}^{\;}$Ϊ30m/s£»
£¨2£©ÁÔ±ªÔÚÕû¸ö¹ý³ÌÖÐÔ˶¯µÄ¾àÀëxΪ390m

µãÆÀ ½â¾ö±¾ÌâµÄ¹Ø¼üÕÆÎÕÔȱäËÙÖ±ÏßÔ˶¯µÄËÙ¶Èʱ¼ä¹«Ê½ºÍËÙ¶ÈλÒƹ«Ê½£¬²¢ÄÜÁé»îÔËÓ㬻ù´¡Ì⣮