Question

3£®ÈçͼËùʾ£¬Ö±¸Ë³¤L₁=0.5m£¬Ô²Í²¸ßΪL₂=3.7m£®Ö±¸ËλÓÚԲͲÕýÉÏ·½H=0.8m´¦£®Ö±¸Ë´Ó¾²Ö¹¿ªÊ¼×ö×ÔÓÉÂäÌåÔ˶¯£¬²¢ÄÜÊúÖ±´©Ô½Ô²Í²£®ÊÔÇó£¨È¡g=10m/s²£©
£¨1£©ÓÉÊͷŵ½Ö±¸Ë϶˸պÿªÊ¼½øÈëԲͲʱ¾­ÀúµÄʱ¼ät₁
£¨2£©Ö±¸Ë´©Ô½Ô²Í²ËùÓõÄʱ¼ät₂£®
£¨3£©ÈôÖ±¸Ë¸Õµ½´ïԲͲÉ϶ËAµãʱ£¬Ô²Í²Í¬Ê±¿ªÊ¼×ÔÓÉÏÂÂ䣬ÉèԲͲÀëµØÃæ×ã¹»¸ß£¬ÇóÖ±¸Ë´©¹ýԲͲËùÓÃʱ¼ät₃ £¨½á¹û±£ÁôÁ½Î»ÓÐЧÊý×Ö£©

Answer 1

·ÖÎö £¨1£©Ö±¸Ë´Ó¿ªÊ¼ÏÂÂäµ½Æä϶˸պýøÈëԲͲ£¬¼´ÏÂÂäλÒÆΪH£¬¸ù¾ÝλÒÆʱ¼ä¹«Ê½¿ÉÇó½â
£¨2£©Ö±¸Ë´Ó¿ªÊ¼ÏÂÂäµ½Æä϶˸պô©³öԲͲ£¬¸ù¾ÝλÒÆʱ¼ä¹«Ê½¿ÉÇó½â
£¨3£©ÀûÓÃλÒÆʱ¼ä¹«Ê½±íʾ³öÁ½Õßͨ¹ýµÄλÒÆ£¬¼´¿ÉÇóµÃʱ¼ä

½â´ð ½â£º£¨1£©ÉèÖ±¸Ë϶˵½´ïԲͲÉÏ·½µÄʱ¼äΪt₁£¬$H=\frac{1}{2}{gt}_{1}^{2}$ 
½âµÃt₁=0.4s
£¨2£©Ö±¸ËÉ϶ËÀ뿪ԲͲÏ·½Ê±¼äΪt£¬${L}_{1}+H+{L}_{2}=\frac{1}{2}g{t}^{2}$
½âµÃt=1s
Ö±¸Ë´©Ô½Ô²Í²ËùÓõÄʱ¼äΪ
t₂=t-t₁=0.6s
£¨3£©Éè´Ë¹ý³ÌÖÐԲͲÏÂÂä¸ß¶ÈΪh₁£¬Ö±¸ËÏÂÂä¸ß¶ÈΪh₂£¬ÈçÓÒͼËùʾ£¬ÓÐh₁+L₁+L₂=h₂
${h}_{1}=\frac{1}{2}{gt}_{3}^{2}$
${h}_{2}={v}_{1}{t}_{3}+\frac{1}{2}{gt}_{3}^{2}$
v₁=gt₁
ÁªÁ¢ÒÔÉϸ÷ʽ½âµÃ£ºt₃=1.05s
´ð£¨1£©ÓÉÊͷŵ½Ö±¸Ë϶˸պÿªÊ¼½øÈëԲͲʱ¾­ÀúµÄʱ¼ät₁Ϊ0.4s
£¨2£©Ö±¸Ë´©Ô½Ô²Í²ËùÓõÄʱ¼ät₂Ϊ0.6s
£¨3£©ÈôÖ±¸Ë¸Õµ½´ïԲͲÉ϶ËAµãʱ£¬Ô²Í²Í¬Ê±¿ªÊ¼×ÔÓÉÏÂÂ䣬ÉèԲͲÀëµØÃæ×ã¹»¸ß£¬ÇóÖ±¸Ë´©¹ýԲͲËùÓÃʱ¼ät₃ Îª1.05s

µãÆÀ ±¾ÌâÖ÷Òª¿¼²éÁË×ÔÓÉÂäÌåÔ˶¯µÄ»ù±¾¹«Ê½µÄÖ±½ÓÓ¦Óã¬ÄѶȲ»´ó£®