Question

ÈçͼËùʾµÄ×ø±êϵxOyÖУ¬x£¼0£¬y£¾0µÄÇøÓòÄÚÓÐÑØxÖáÕý·½ÏòµÄÔÈÇ¿µç³¡£¬x¡Ý0µÄÇøÓòÄÚÓд¹Ö±ÓÚxOy×ø±êƽÃæÏòÍâµÄÔÈÇ¿´Å³¡£¬xÖáÉÏAµã×ø±êΪ£¨£­L£¬0£©£¬yÖáÉÏBµãµÄ×ø±êΪ£¨0£¬£©¡£ÓÐÒ»¸ö´øÕýµçµÄÁ£×Ó´ÓAµãÒÔ³õËÙ¶Èv_AÑØyÖáÕý·½ÏòÉäÈëÔÈÇ¿µç³¡ÇøÓò£¬¾­¹ýBµã½øÈëÔÈÇ¿´Å³¡ÇøÓò£¬È»ºó¾­xÖáÉϵÄCµã£¨Í¼ÖÐδ»­³ö£©Ô˶¯µ½×ø±êÔ­µãO¡£²»¼ÆÖØÁ¦¡£Çó£º

£¨1£©Á£×ÓÔÚBµãµÄËÙ¶Èv_BÊǶà´ó£¿

£¨2£©CµãÓëOµãµÄ¾àÀëx_cÊǶà´ó£¿

£¨3£©ÔÈÇ¿µç³¡µÄµç³¡Ç¿¶ÈÓëÔÈÇ¿´Å³¡µÄ´Å¸ÐӦǿ¶ÈµÄ±ÈÖµÊǶà´ó£¿

Answer 1

½â£º

(1)ÉèÁ£×ÓÔÚAµ½BµÄ¹ý³ÌÖÐÔ˶¯Ê±¼äΪt£¬ÔÚBµãʱËÙ¶ÈÑØxÖáÕý·½ÏòµÄËٶȴóСΪv_x£¬Ôò

                                                   ¡­¡­¡­¡­£¨1·Ö£©

                                                  ¡­¡­¡­¡­£¨1·Ö£©

                                           ¡­¡­¡­¡­£¨2·Ö£©

½âµÃv_B£½2v_A                                             ¡­¡­¡­¡­£¨1·Ö£©

(2)ÉèÁ£×ÓÔÚBµãµÄËÙ¶Èv_BÓëyÖáÕý·½ÏòµÄ¼Ð½ÇΪ¦È£¬Ôò

                                                 ¡­¡­¡­¡­£¨2·Ö£©

½âµÃ¦È£½60º

Á£×ÓÔÚx¡Ý0µÄÇøÓòÄÚ×öÔÈËÙÔ²ÖÜÔ˶¯£¬Ô˶¯¹ì¼£ÈçͼËùʾ£¬Éè¹ìµÀ°ë¾¶ÎªR£¬Óɼ¸ºÎ¹ØϵÓÐ

                                       ¡­¡­¡­¡­¡­¡­¡­¡­¡­£¨2·Ö£©

x_c£½2Rcos¦È                                                 ¡­¡­¡­¡­¡­¡­¡­¡­¡­£¨2·Ö£©

x_c£½2L/3                                                     ¡­¡­¡­¡­¡­¡­¡­¡­¡­£¨1·Ö£©

(»òÕßͨ¹ýÅжÏBC ÊÇÖ±¾¶£¬¡÷OO₁CÊǵȱßÈý½ÇÐΣ¬ÓÉx_c£½RµÃµ½x_c£½2L/3)

(3) ÉèÔÈÇ¿µç³¡Ç¿¶ÈΪE£¬ÔÈÇ¿´Å³¡µÄ´Å¸ÐӦǿ¶ÈΪB£¬Á£×ÓÖÊÁ¿Îªm£¬´øµçºÉÁ¿Îªq£¬Ôò

                                 ¡­¡­¡­¡­¡­¡­¡­¡­¡­£¨2·Ö£©

                                            ¡­¡­¡­¡­¡­¡­¡­¡­¡­£¨2·Ö£©

½âµÃ                                             ¡­¡­¡­¡­¡­¡­¡­¡­¡­£¨1·Ö£©