Question

10£®Èçͼ£¬Ò»Ë®Æ½´«ËÍ´øÒÔ4.0m/sµÄËÙ¶È˳ʱÕë´«ËÍ£¬Ë®Æ½²¿·Ö³¤L=5.0m£¬ÆäÓÒ¶ËÓëÒ»Çã½ÇΪ¦È=37¡ãµÄбÃæƽ»¬ÏàÁ¬£¬ÒÑÖªÎï¿éÓëбÃæµÄ¶¯Ä¦²ÁÒòËØΪ¦Ì₁=0.5£®ÏÖÓÐÒ»¿ÉÊÓΪÖʵãµÄÎï¿éÎÞ³õËٵطÅÔÚ´«ËÍ´ø×î×ó¶Ë£¬ÒÑÖªÎï¿éÓë´«ËÍ´ø¼äµÄ¶¯Ä¦²ÁÒòËØΪ¦Ì₂=0.2£®£¨¼ÙÉèÎï¿éÔÚˮƽÃæºÍбÃæµÄתÕÛ´¦Îï¿éµÄËٶȴóС²»¸Ä±ä£©£®
£¨1£©ÊÔÇóÎï¿é´Ó´«ËÍ´ø×î×ó¶Ëµ½´ï×îÓÒ¶ËËùÐèÒªµÄʱ¼äÊǶàÉÙ£¿
£¨2£©Îï¿é³åÉÏбÃæºó£¬ÔÚбÃæÉÏÏòÉÏ»¬ÐеļÓËٶȵĴóС£¿
£¨3£©Îï¿é³åÉÏбÃæºó£¬ÔÚбÃæÉÏÄÜÏòÉÏ»¬ÐеÄ×îÔ¶¾àÀëÊǶàÉÙ£¿

Answer 1

·ÖÎö £¨1£©Îï¿éÎÞ³õËٵطÅÔÚ´«ËÍ´ø×î×ó¶Ë£¬ÏÈ×öÔȼÓËÙÔ˶¯£¬ÓÉÅ£¶ÙµÚ¶þ¶¨ÂɺÍÔ˶¯Ñ§¹«Ê½½áºÏÇó³ö¼ÓËÙµ½ËÙ¶ÈÓë´«ËÍ´øÏàͬËùÓÃʱ¼ä£¬ÒÔ¼°Í¨¹ýµÄλÒÆ£®ÔÙÇóÔÈËÙÔ˶¯µÄʱ¼ä£¬´Ó¶øµÃµ½×Üʱ¼ä£®
£¨2£©Îï¿é³åÉÏбÃæºó×öÔȼõËÙÔ˶¯£¬ÓÉÅ£¶ÙµÚ¶þ¶¨ÂÉÇó¼ÓËٶȣ®
£¨3£©ÓÉËÙ¶ÈλÒƹ«Ê½ÇóÎï¿éÉÏ»¬µÄ×îÔ¶¾àÀ룮

½â´ð ½â£º£¨1£©Îï¿éÔÚ´«ËÍ´øÉÏÏȼÓËÙÔ˶¯ºóÔÈËÙÔ˶¯£®
¸ù¾ÝÅ£¶ÙµÚ¶þ¶¨Âɵãº
ÔȼÓËÙÔ˶¯µÄ¼ÓËÙ¶ÈΪ a₁=$\frac{{¦Ì}_{1}mg}{m}$
¿ÉµÃ ${a_1}={¦Ì_2}g=2m/{s^2}$
ÔȼÓËÙÔ˶¯µÄʱ¼ä£º${t_1}=\frac{v}{a_1}=2s$
ÔȼÓËÙÔ˶¯µÄ¾àÀëΪ£º${S_1}=\frac{1}{2}a{t_1}^2=4m$
ÔÈËÙÔ˶¯µÄʱ¼ä£º${t_2}=\frac{{L-{S_1}}}{v}=0.25s$
¹Ê×Üʱ¼ä t=t₁+t₂=2.25s
£¨2£©Îï¿éÒÔ4m/sµÄËٶȻ¬ÉÏбÃæºó¼ÓËÙ¶ÈΪ£º
  ${a_2}=-\frac{mgsin¦È+¦Ìmgcos¦È}{m}=-10m/{s^2}$£¬¼ÓËٶȴóСΪ10m/s²£®
£¨3£©Îï¿éÉÏ»¬µÄ×î´ó¾àÀëÉèΪx£¬Ôò£º0-v²=2a₂x
¿ÉµÃ $x=\frac{v^2}{{2{a_2}}}=0.8m$
´ð£º
£¨1£©ÊÔÇóÎï¿é´Ó´«ËÍ´ø×î×ó¶Ëµ½´ï×îÓÒ¶ËËùÐèÒªµÄʱ¼äÊÇ2.25s£®
£¨2£©Îï¿é³åÉÏбÃæºó£¬ÔÚбÃæÉÏÏòÉÏ»¬ÐеļÓËٶȵĴóСÊÇ10m/s²£®
£¨3£©Îï¿é³åÉÏбÃæºó£¬ÔÚбÃæÉÏÄÜÏòÉÏ»¬ÐеÄ×îÔ¶¾àÀëÊÇ0.8m£®

µãÆÀ ½â¾ö±¾ÌâµÄ¹Ø¼üÀíÇåÎï¿éÔÚÕû¸ö¹ý³ÌÖеÄÔ˶¯Çé¿ö£¬½áºÏÅ£¶ÙµÚ¶þ¶¨ÂÉ¡¢Ô˶¯Ñ§¹«Ê½×ÛºÏÇó½â£®