Question

ÈçͼËùʾ£¬Á½¿é×ã¹»´óµÄƽÐнðÊô°åa¡¢bÊúÖ±·ÅÖ㬰å¼äÓг¡Ç¿ÎªEµÄÔÈÇ¿µç³¡£¬Á½°å¾àÀëΪd£¬½ñÓÐÒ»´øÕýµç΢Á£´Óa°åϱßÔµÒÔ³õËÙ¶Èv₀ÊúÖ±ÏòÉÏÉäÈë°å¼ä£¬µ±Ëü·Éµ½b°åʱ£¬ËٶȴóС²»±ä£¬¶ø·½Ïò±äΪˮƽ·½Ïò£¬ÇҸպôӸ߶ÈҲΪdµÄÏÁ·ì´©¹ýb°å¶ø½øÈëbcÇøÓò£¬bcÇøÓòµÄ¿í¶ÈҲΪd£¬Ëù¼Óµç³¡´óСΪE£¬·½ÏòÊúÖ±ÏòÉÏ£¬´Å¸ÐӦǿ¶È£¬·½Ïò´¹Ö±Ö½ÃæÏòÀï¡£Çó£º

£¨1£©Î¢Á£µÄ´øµçÁ¿q£»

£¨2£©Î¢Á£´©³öbcÇøÓòµÄλÖõ½a°åϱßÔµµÄÊúÖ±¾àÀëL£¨ÓÃd±íʾ£©£»

£¨3£©Î¢Á£ÔÚab¡¢bcÇøÓòÖÐÔ˶¯µÄ×Üʱ¼ät£¨ÓÃd¡¢v₀±íʾ£©¡£

 

Answer 1

£¨1£©  £¨2£©   £¨3£©

½âÎö:£¨1£©Î¢Á£Ôڵ糡ÖÐÊÜˮƽÏòÓҵĵ糡Á¦ºÍÊúÖ±ÏòϵÄÖØÁ¦£¬ÆäÔ˶¯·Ö½âΪˮƽºÍÊúÖ±µÄÔȱäËÙÔ˶¯£¬Ë®Æ½·½Ïò¼ÓËÙ¶È a=£¬£¨2·Ö£©

ÓÖ   £¬£¨2·Ö£©

µÃ  £¨1·Ö£©

£¨ÓÉa=£¬£¬µÃ£¬Í¬Ñù¸ø5·Ö£©

£¨2£©Î¢Á£½øÈëbcÇøÓòÖÐÓÉÓڵ糡Á¦ÓëÖØÁ¦Æ½ºâ£¬Î¢Á£ÔÚÂåÂØ×ÈÁ¦×÷ÓÃÏÂ×öÔÈËÙÔ²ÖÜÔ˶¯£¬

£¨1·Ö£©

ÓÖ£¬d=£¨2·Ö£©

µÃÔ²Öܰ뾶r=2d£¬£¨2·Ö£©

΢Á£¸Õ½øÈëbcʱÂåÂ××ÈÁ¦·½ÏòÏòÉÏ£¬ÄæʱÕëƫת£¬¹ì¼£ÈçͼËùʾ¡£ÉèÔ²ÐĽÇΪ¦È£¬Óɼ¸ºÎ¹ØϵµÃ

sin¦È=£¬   £¨1·Ö£©

¼´ ¦È=30¡ã    £¨1·Ö£©

΢Á£´©³öbcÇøÓòµÄλÖõ½a°åϱßÔµµÄÊúÖ±¾àÀë

L=d+ r£¨1-cos30¡ã£©=£¨3£©d      £¨2·Ö£©

£¨3£©Î¢Á£Ôڵ糡ÖеÄÔ˶¯Ê±¼äΪ£¬     £¨2·Ö£©

´Å³¡ÖÐÔ˶¯Ê±¼ä£¬     £¨2·Ö£©

ÔÚab¡¢bcÇøÓòÖÐÔ˶¯µÄ×Üʱ¼äΪ=    £¨1·Ö£©¡¢