ÌâÄ¿ÄÚÈÝ

ÈçͼËùʾ£¬ÔÚÊúÖ±ÏòÏ£¬³¡Ç¿ÎªEµÄÔÈÇ¿µç³¡ÖУ¬³¤ÎªlµÄ¾øÔµÇá¸Ë¿ÉÈƹ̶¨ÖáOÔÚÊúÖ±ÃæÄÚÎÞĦ²Áת¶¯£¬Á½¸öСÇòA¡¢B¹Ì¶¨Óڸ˵ÄÁ½¶Ë£¬A¡¢BµÄÖÊÁ¿·Ö±ðΪm1ºÍm2£¨m1£¼m2£©£¬A´ø¸ºµç£¬µçÁ¿Îªq1£¬B´øÕýµç£¬µçÁ¿Îªq2£®¸Ë´Ó¾²Ö¹¿ªÊ¼ÓÉˮƽλÖÃתµ½ÊúֱλÖã¬Çó£º
£¨1£©Ôڴ˹ý³ÌÖе糡Á¦Ëù×öµÄ¹¦Îª¶àÉÙ£¿
£¨2£©ÔÚÊúֱλÖô¦Á½ÇòµÄ×ܶ¯ÄÜΪ¶àÉÙ£¿
Èô½«Çá¸ËÍäÕÛ³ÉÈçͼËùʾµÄ¡°¦£¡±ÐΣ¬Á½±ß»¥Ïà´¹Ö±¡¢³¤¶È¾ùΪ
1
2
£¬Á½¶Ë¸÷¹Ì¶¨Ò»¸ö½ðÊôСÇòA¡¢B£¬ÔÚÊúÖ±ÏòÏ£¬³¡Ç¿ÎªEµÄÔÈÇ¿µç³¡ÖУ¬¿ÉÈƹýOµãµÄˮƽÖáÔÚÊúֱƽÃæÄÚÎÞĦ²Áת¶¯£®ÒÑÖªAÇòÖÊÁ¿m1=m£¬µçÁ¿Îª+q£¬BÇòÖÊÁ¿m2=7m/2£¬BÇòÒ²´ø¸ºµç£¬µçÁ¿Îª-q£®ÏÖ½«¡°¦£¡±Ðθ˴ÓOBλÓÚˮƽλÖÃÓɾ²Ö¹ÊÍ·Å£¬Çó£º
£¨3£©OB¸ËÄÜת¹ýµÄ×î´ó½Ç¶ÈΪ127¡ã£¬Ôò¸Ãµç³¡Ç¿¶ÈµÄ´óСΪ¶àÉÙ£¿
£¨4£©µ±Á½ÇòµÄËٶȴﵽ×î´óʱ£¬OB¸Ëת¹ýµÄ½Ç¶ÈΪ¶à´ó£¿
£¨1£©ÒòΪ¸Ë¼°ABÊÜÁ¦µÄºÏÁ¦¾ØΪ˳ʱÕ룬ËùÒÔϵͳÑØ˳ʱÕëת¶¯µ½ÊúֱλÖ㬵糡Á¦¶ÔAºÍB¶¼×öÕý¹¦£¬µç³¡Á¦¶ÔA¡¢B×ö×ܹ¦Îª£º
WE=q2E¡Á
L
2
+q1E¡Á
L
2
=
1
2
£¨q1+q2£©EL£¬
£¨2£©Ôڴ˹ý³ÌÖÐÖØÁ¦¶ÔA×öÕý¹¦£¬¶ÔB×ö¸º¹¦£¬WG=m2g¡Á
L
2
-m1g¡Á
L
2
=
1
2
£¨m2-m1£©gL£¬
ÉèÁ½Çò×ܶ¯ÄÜΪEk£¬ÓÉÓö¯Äܶ¨ÀíµÃ£º
Ek-0=WE+WG=
1
2
£¨q1E+q2E+m2g-m1g£©L£¬
£¨3£©´ÓOBλÓÚˮƽλÖÃÓɾ²Ö¹Êͷŵ½OB¸ËÄÜת¹ýµÄ½Ç¶ÈΪ127¡ã£¬¸ù¾Ý¶¯Äܶ¨ÀíÁгöµÈʽ
3.5mg¡Á0.8¡Á
1
2
L-mg¡Á1.6¡Á
1
2
L-qE¡Á0.8¡Á
1
2
L-qE¡Á1.6¡Á
1
2
L=0-0=0
½âµÃ£ºE=
mg
2q

£¨4£©Ëٶȴﵽ×î´óʱÁ¦¾Øƽºâ£¬Éèת¹ýµÄ½Ç¶ÈΪ¦È£¬¸ù¾ÝÁ¦¾Øƽºâ·½³ÌµÃ
£¨qE+mg£©sin¦È=£¨3.5mg-qE£©cos¦È£¬
½âµÃtan¦È=2£¬¼´OB¸Ëת¹ýµÄ½Ç¶ÈµÄÕýÇÐÖµÊÇ2£®
´ð£º£¨1£©Ôڴ˹ý³ÌÖе糡Á¦Ëù×öµÄ¹¦Îª
1
2
£¨q1+q2£©EL
£¨2£©ÔÚÊúֱλÖô¦Á½ÇòµÄ×ܶ¯ÄÜΪ
1
2
£¨q1E+q2E+m2g-m1g£©L£¬
£¨3£©OB¸ËÄÜת¹ýµÄ×î´ó½Ç¶ÈΪ127¡ã£¬Ôò¸Ãµç³¡Ç¿¶ÈµÄ´óСΪ
mg
2q

£¨4£©OB¸Ëת¹ýµÄ½Ç¶ÈµÄÕýÇÐÖµÊÇ2£®
Á·Ï°²áϵÁдð°¸
Ïà¹ØÌâÄ¿

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

¾«Ó¢¼Ò½ÌÍø