Question

£¨19·Ö£©ÈçͼËùʾ£¬ÀëµØÃæ×ã¹»¸ß´¦ÓÐÒ»ÊúÖ±µÄ¿Õ¹Ü£¬ÖÊÁ¿Îª2kg£¬¹Ü³¤Îª24m£¬M¡¢NΪ¿Õ¹ÜµÄÉÏ¡¢ÏÂÁ½¶Ë£¬¿Õ¹ÜÊܵ½F=16NÊúÖ±ÏòÉϵÄÀ­Á¦×÷Óã¬Óɾ²Ö¹¿ªÊ¼ÊúÖ±ÏòÏÂ×ö¼ÓËÙÔ˶¯£¬Í¬Ê±ÔÚM´¦Ò»¸ö´óС²»¼ÆµÄСÇòÑعܵÄÖáÏßÒÔ³õËÙ¶Èv₀ÊúÖ±ÉÏÅ×£¬²»¼ÆÒ»ÇÐ×èÁ¦£¬È¡g=10m/s²£®Çó£º

£¨1£©ÈôСÇòÉÏÅ׵ijõËÙ¶ÈΪ10m/s£¬¾­¹ý¶à³¤Ê±¼ä´Ó¹ÜµÄN¶Ë´©³ö£¿

£¨2£©Èô´Ë¿Õ¹ÜµÄN¶Ë¾àÀëµØÃæ64m¸ß£¬ÓûʹÔڿչܵ½´ïµØÃæʱСÇò±ØÐëÂäµ½¹ÜÄÚ£¬ÔÚÆäËûÌõ¼þ²»±äµÄÇ°ÌáÏ£¬ÇóСÇòµÄ³õËÙ¶Èv₀´óСµÄ·¶Î§£®

Answer 1

£¨19·Ö£©½âÎö£º£¨1£©£¨5·Ö£©ÒÔÏòÏ·½ÏòΪÕý·½Ïò¡£

¶Ô¿Õ¹Ü£¬ÓÉÅ£¶ÙµÚ¶þ¶¨ÂɿɵÃmg£­F=ma£¬µÃa=2m/s²¡­¡­¢Ù £¨2·Ö£©

Éè¾­tʱ¼ä£¬Ð¡Çò´ÓN¶Ë´©³ö£¬Ð¡ÇòÏÂÂäµÄ¸ß¶Èh₁=£­v₀t+gt²¡­¡­¡­¢Ú   £¨2·Ö£©

¿Õ¹ÜÏÂÂäµÄ¸ß¶Èh₂=at²¡­¡­¡­¡­¡­¢Û                               £¨2·Ö£©

Ôò£¬h₁£­h₂=L¡­¡­¡­¡­¡­¢Ü

ÁªÁ¢µÃ£º£­v₀t+gt²£­at²=L¡­¡­¡­¡­¡­¢Ý                            £¨2·Ö£©

´úÈëÊý¾Ý½âµÃ£ºt=4s£¬t=£­1.5s£¨Éᣩ¡­¡­¡­¡­¡­¡­¡­¢Þ                  £¨2·Ö£©

£¨2£©£¨7·Ö£©ÉèСÇò³õËÙ¶Èv₀£¬¿Õ¹Ü¾­t'ʱ¼äµ½´ïµØÃ棬ÔòH=at'²¡­¡­¡­¡­¡­¡­¡­¢ß

µÃt'==8s¡­¡­¡­¡­¡­¡­¢à                                       £¨2·Ö£©

СÇòÔÚt'ʱ¼äÏÂÂä¸ß¶ÈΪh=£­v₀t'+gt'²¡­¡­¡­¡­¡­¢á                      £¨2·Ö£©

СÇòÂäÈë¹ÜÄÚµÄÌõ¼þÊÇ£º64m¡Üh¡Ü88m                                   £¨3·Ö£©

½âµÃ£º29m/s¡Üv₀¡Ü32m/s

ËùÒÔСÇòµÄ³õËٶȴóС±ØÐëÔÚ29m/sµ½32m/s·¶Î§ÄÚ£®                   £¨2·Ö£©