ÌâÄ¿ÄÚÈÝ

ÈçͼËùʾ£¬ÔÚˮƽµØÃæÉϹ̶¨Ò»Çã½ÇΪ¦È=37¡ãµÄ×ã¹»³¤Ð±Ã森ÖÊÁ¿¾ùΪm=0.3kgµÄÁ½Îï¿éAºÍBÖÃÓÚбÃæÉÏ£¬ÒÑÖªÎï¿éAÓëбÃæÖ®¼äÎÞĦ²Á£¬Îï¿éBÓëбÃæ¼äµÄ¶¯Ä¦²ÁÒòÊýΪ¦Ì=0.75£®¿ªÊ¼Ê±ÓÃÊÖ°´×¡AºÍB£¬Ê¹A¾²Ö¹ÔÚбÃ涥¶Ë£¬Îï¿éB¾²Ö¹ÔÚÓëAÏà¾àl=5.0cmµÄбÃæÏ·½£®ÏÖͬʱÇáÇáËÉ¿ªÁ½ÊÖ£¬ÇÒͬʱÔÚÎï¿éAÉÏÊ©¼ÓÒ»¸öÊúÖ±ÏòϵĴóСΪ2NµÄºãÁ¦F£¬¾­Ò»¶Îʱ¼äºóAºÍB·¢ÉúÕýÅö£®¼ÙÉèÔÚ¸÷´ÎÅöײ¹ý³ÌÖУ¬Ã»ÓлúеÄÜËðʧ£¬ÇÒÅöײʱ¼ä¼«¶Ì¿ÉºöÂÔ²»¼Æ£®ÉèÔÚ±¾ÌâÖÐ×î´ó¾²Ä¦²ÁÁ¦µÈÓÚ»¬¶¯Ä¦²ÁÁ¦£¬gÈ¡10m/s2£®ÒÑÖªsin37¡ã=0.6£¬cos37¡ã=0.8£¬Çó£º
£¨1£©µÚÒ»´ÎÅöײ½áÊø˲¼äÎï¿éA¡¢BµÄËٶȸ÷¶à´ó£¿
£¨2£©´Ó·ÅÊÖ¿ªÊ¼µ½¼´½«·¢ÉúµÚ¶þ´ÎÅöײµÄÕâ¶Îʱ¼äÄÚ£¬ºãÁ¦F¶ÔÎï¿éA×öÁ˶àÉÙ¹¦£¿
·ÖÎö£º£¨1£©·ÅÊÖºó£¬ÓÉÓÚBµÄÖØÁ¦·ÖÁ¦µÈÓÚ×î´ó¾²Ä¦²ÁÁ¦£¬ËùÒÔB´¦ÓÚ¾²Ö¹£¬A×öÔȼÓËÙÔ˶¯£¬¸ù¾Ý¶¯Äܶ¨ÀíÇó³öAÓëBÅöײǰµÄËٶȣ¬ÔÙ¸ù¾Ý¶¯Á¿Êغ㶨ÂɺͻúеÄÜÊغ㶨ÂÉÇó³öÅöײºó˲¼äA¡¢BµÄËٶȣ®
£¨2£©µÚÒ»´ÎÅöºó£¬A×öÔȼÓËÙÖ±ÏßÔ˶¯£¬B×öÔÈËÙÖ±ÏßÔ˶¯£¬×¥×¡Î»ÒÆÏàµÈ£¬Çó³öµÚ¶þ´ÎÏàײǰAµÄλÒÆ£¬´Ó¶øµÃ³öAµÄ×ÜλÒÆ£¬¸ù¾ÝºãÁ¦×ö¹¦µÄ¹«Ê½Çó³öºãÁ¦F¶ÔÎï¿éA×öµÄ¹¦£®
½â´ð£º½â£º£¨1£©·ÅÊÖºó£¬B´¦ÓÚ¾²Ö¹×´Ì¬£¬A×öÔȼÓËÙÔ˶¯£¬ÉèµÚÒ»´ÎÅöÇ°£¬AµÄËÙ¶ÈΪvA1
Óɶ¯Äܶ¨Àí (F+mg)lsin370=
1
2
m
v
2
A1

´øÈëÊý¾ÝµÃvA=1m/s
A¡¢B·¢ÉúµÚÒ»´ÎÅöײ¹ý³ÌÖÐÓɶ¯Á¿ÊغãºÍ»úеÄÜÊغãÓÐ
 mvA1=mvA1¡ä+mvB1¡ä
1
2
m
v
2
A1
=
1
2
m
v
¡ä  2
A1
+
1
2
vm
¡ä 2
B1
                             
´øÈëÊý¾ÝµÃvA1¡ä=0£» VB1¡ä=1m/s
´ð£ºµÚÒ»´ÎÅöºóA¡¢BµÄËٶȷֱðΪvA1¡ä=0£»vB1¡ä=1m/s£®   
£¨2£©µÚÒ»´ÎÅöײºó
¶ÔA    ÓÉÅ£¶ÙµÚ¶þ¶¨ÂÉ£¨F+mg£©sin37¡ã=ma   µÃa=10m/s2  ¿ÉÖª
A×ö³õËÙ¶ÈΪ0¼ÓËÙ¶ÈΪ a=10m/s2ÔȼÓËÙÔ˶¯     
¶ÔBÊÜÁ¦·ÖÎö¿ÉÖªBÒÔ 1m/sËÙ¶È×öÔÈËÙÔ˶¯        
ÉèµÚ¶þ´ÎÅöײǰA¡¢BµÄËٶȷֱðΪvA2£¬vB2£¬ÆäÖУ®ÓÉA¡¢B·¢ÉúµÚÒ»´ÎÅöײµ½·¢ÉúµÚ¶þ´ÎÅöײλÒÆÏàµÈÓÐ
   s2=
vA2
2
t=vB2t
                   
µÃ  vA2=2m/s
ÕâÒ»¹ý³ÌµÄAµÄλÒÆ s2=
vA2
2a
             
ÁªÁ¢µÃ s2=0.2m  
´Ó·ÅÊÖµ½¼´½«·¢ÉúµÚ¶þ´ÎÅöײµÄ¹ý³ÌÖУ¬Á¦F×ö¹¦Îª
 WF=F£¨l+S2£©sin37¡ã=0.3J      
´ð£ººãÁ¦F¶ÔÎï¿éA×öÁË0.3JµÄ¹¦£®
µãÆÀ£º±¾Ìâ¹ý³Ì½Ï¶à£¬¹Ø¼üÊÇÀíÇåÿһ½×¶ÎµÄÔ˶¯Çé¿ö£¬½áºÏ¶¯Äܶ¨Àí¡¢»úеÄÜÊغ㶨ÂɺͶ¯Á¿Êغ㶨ÂɽøÐÐÇó½â£®
Á·Ï°²áϵÁдð°¸
Ïà¹ØÌâÄ¿

Î¥·¨ºÍ²»Á¼ÐÅÏ¢¾Ù±¨µç»°£º027-86699610 ¾Ù±¨ÓÊÏ䣺58377363@163.com

¾«Ó¢¼Ò½ÌÍø