ÌâÄ¿ÄÚÈÝ
3£®ÈçͼËùʾ£¬Çã½Ç¦È=37¡ãµÄ´Ö²ÚбÃæ¹Ì¶¨ÔÚˮƽÃæÉÏ£¬ÖÊÁ¿m=2.0kgµÄÎï¿é£¨¿ÉÊÓΪÖʵ㣩£¬ÔÚÑØбÃæÏòÉϵÄÀÁ¦F×÷ÓÃÏ£¬Óɾ²Ö¹¿ªÊ¼´ÓбÃæµ×¶ËÑØбÃæÏòÉÏÔ˶¯£®ÒÑÖªÀÁ¦F=32N£¬Îï¿éÓëбÃæ¼äµÄ¶¯Ä¦²ÁÒòÊýΪ¦Ì=0.25£¬sin37¡ã=0.6£¬cos37¡ã=0.8£¬ÇÒбÃæ×ã¹»³¤£®È¡ÖØÁ¦¼ÓËÙ¶Èg=10m/s2£¬Ç󣺣¨1£©Îï¿é¼ÓËٶȵĴóС£»
£¨2£©ÈôÔÚµÚ2.0sÄ©³·È¥ÀÁ¦F£¬Îï¿éÀëбÃæµ×¶ËµÄ×î´ó¾àÀ룮
·ÖÎö £¨1£©¶ÔÎï¿é½øÐÐÊÜÁ¦·ÖÎö£¬ÓÉÅ£¶ÙµÚ¶þ¶¨ÂÉÁÐʽ¼´¿ÉÇó½â£»
£¨2£©¸ù¾ÝµÚÒ»Îʵıí´ïʽÇó³öÔȼÓËÙÉÏÉýºÍÔȼõËÙÉÏÉýµÄ¼ÓËٶȣ¬¸ù¾ÝÔ˶¯Ñ§»ù±¾¹«Ê½Çó³öÉÏÉýµÄ×ÜλÒÆ£»
½â´ð ½â£º£¨1£©Îï¿éµÄÊÜÁ¦Çé¿öÈçͼ1Ëùʾ£®ÓÉÅ£¶ÙµÚ¶þ¶¨ÂÉÓУº
F-mgsin¦È-f=ma1¡¢Ù
N-mgcos¦È=0¡¢Ú
ÓÖÒòΪ f=¦ÌN¡¢Û
ÓÉ¢Ù¢Ú¢Ûʽ¿ÉÇóµÃ£ºa1=8.0m/s2
£¨2£©Îï¿é×ö³õËÙ¶ÈΪÁãµÄÔȼÓËÙÖ±ÏßÔ˶¯£¬µÚ2.0sĩʱÎï¿éµÄËÙ¶ÈΪ£º
v1=a1t1=8¡Á2=16m/s
Õâ2.0sÄÚÎï¿éµÄλÒÆ£ºx1=$\frac{1}{2}$a1t12=$\frac{1}{2}¡Á8¡Á4$=16m
³·È¥ÀÁ¦Fºó£¬Îï¿éµÄÊÜÁ¦Çé¿öÈçͼ2Ëùʾ£®
ÓÉÅ£¶ÙµÚ¶þ¶¨ÂÉÓУºmgsin¦È+f=ma2¡¢Ü
ÓÉ¢Ú¢Û¢Üʽ¿ÉÇóµÃ£ºa2=8.0m/s2
Îï¿é×öÔȼõËÙÖ±ÏßÔ˶¯£¬µ½´ï×î¸ßµãʱ£¬ËÙ¶ÈΪÁ㣬
ÔòÓÐv2=2a2x2
½âµÃ£ºx2=16m
ËùÒÔÎï¿éµ½Ð±Ãæµ×¶ËµÄ¾àÀ룺x=x1+x2=16+16=32m
´ð£º£¨1£©Îï¿é¼ÓËٶȵĴóСΪ8.0m/s2£»
£¨2£©ÈôÔÚµÚ2.0sÄ©³·È¥ÀÁ¦F£¬Îï¿éÀëбÃæµ×¶ËµÄ×î´ó¾àÀëΪ32m
µãÆÀ ±¾ÌâÖ÷Òª¿¼²ìÁËÅ£¶ÙµÚ¶þ¶¨Âɼ°Ô˶¯Ñ§»ù±¾¹«Ê½µÄÖ±½ÓÓ¦Óã¬×¥×¡ÔȼÓËÙÔ˶¯µÄÄ©Ëٶȼ´ÎªÔȼõËÙÔ˶¯µÄ³õËÙ¶ÈÁÐʽ£¬×¢ÒâÕýÈ·ÊÜÁ¦·ÖÎö´Ó¶øÇó½â¼ÓËٶȣ®
A£® | AËùÐèµÄÏòÐÄÁ¦±ÈBµÄ´ó | |
B£® | ÇáÖÊϸÏ߶ÔBµÄÀÁ¦±ÈϸÏ߶ÔAÀÁ¦´ó | |
C£® | AµÄ½ÇËٶȱÈBµÄ´ó | |
D£® | A¡¢BµÄ½ÇËٶȴóСÏàµÈ |
A£® | ÎïÌåÄÚËùÓзÖ×ÓÈÈÔ˶¯µÄ·Ö×Ó¶¯ÄܵÄ×ܺÍΪÎïÌåµÄÄÚÄÜ | |
B£® | Òº¾§ÏÔʾÆ÷ÀûÓÃÁËÒº¾§¶Ô¹â¾ßÓи÷ÏîÒìÐÔµÄÌصãÀ´¹¤×÷ | |
C£® | Ò¶ÃæÉϵÄС¶Öé³ÊÇòÐÎÊÇÓÉÓÚÒºÌå±íÃæÕÅÁ¦µÄ×÷Óà | |
D£® | ²¼ÀÊÔ˶¯²»ÊÇÒºÌå·Ö×ÓµÄÔ˶¯£¬¶øÊÇÒºÌå·Ö×ÓÓÀ²»Í£Ï¢ÎÞ¹æÔòÔ˶¯µÄ·´Ó³ | |
E£® | µ±Á½·Ö×Ó¼ä¾àÀë´óÓÚƽºâλÖõļä¾àr0ʱ£¬·Ö×Ó¼äµÄ¾àÀëÔ½´ó£¬·Ö×ÓÊÆÄÜԽС |
A£® | Èô¶Ï¿ª¿ª¹ØS£¬µçÈÝÆ÷Ëù´øµçºÉÁ¿±ä´ó£¬´øµç΢Á£ÏòÉÏÔ˶¯ | |
B£® | Ö»°Ñ±ä×èÆ÷R3µÄ»¬¶¯¶ËP2ÏòÉ϶ËÒƶ¯Ê±£¬µçѹ±íʾÊý±ä´ó£¬´øµç΢Á£ÏòÏÂÔ˶¯ | |
C£® | Ö»µ÷½Úµç×èR2µÄ»¬¶¯¶ËP1Ïò϶ËÒƶ¯Ê±£¬µçѹ±íʾÊý±ä´ó£¬´øµç΢Á£ÏòÉÏÔ˶¯ | |
D£® | Ö»Ôö´óR1µÄ¹âÕÕÇ¿¶È£¬µç×èR0ÏûºÄµÄµç¹¦Âʱä´ó£¬µç×èR3ÖÐÓÐÏòÉϵĵçÁ÷ |
A£® | a±Èbºó×ÅµØ | B£® | aÓëc¿ÉÄÜͬʱ×ÅµØ | ||
C£® | aºÍb¿ÉÄÜͬʱ×ÅµØ | D£® | a¡¢b¡¢c×ŵØʱËٶȴóС¿ÉÄÜÏàµÈ |
A£® | СÇòBÖÊÁ¿Îª$\frac{\sqrt{3}}{3}$m | |
B£® | СÇòBÖÊÁ¿Îª$\frac{2\sqrt{3}}{3}$m | |
C£® | СÇòAµ½´ïC´¦Ê±µÄ¼ÓËÙ¶ÈΪg | |
D£® | СÇòAÉÏÉý¹ý³ÌÖÐÓëСÇòBËٶȴóСʼÖÕÏàµÈ |
A£® | fA£¾fB | B£® | fA£¼fB | ||
C£® | fA=fB | D£® | Ìõ¼þ²»×㣬ÎÞ·¨ÅÐ¶Ï |