ÌâÄ¿ÄÚÈÝ
£¨14·Ö£©ÈçͼËùʾ£¬Ò»Íæ¹öÖáÁï±ùµÄСº¢£¨¿ÉÊÓΪÖʵ㣩ÖÊÁ¿m=30 kg£¬ËûÔÚ×ó²àƽ̨ÉÏ»¬ÐÐÒ»¶Î¾àÀëºóÑØˮƽ·½ÏòÅ׳ö£¬Ç¡ÄÜÎÞÄÜÁ¿ËðʧµØ´ÓAµãÑØÇÐÏß·½Ïò½øÈë¹â»¬ÊúÖ±Ô²»¡¹ìµÀ²¢ÑعìµÀÏ»¬¡£ÒÑÖªA¡¢BΪԲ»¡µÄÁ½¶Ëµã£¬ÆäÁ¬Ïßˮƽ£»Ô²»¡°ë¾¶R=1.0 m£¬¶ÔÓ¦Ô²ÐĽÇ=106¡ã£»Æ½Ì¨ÓëA¡¢BÁ¬Ïߵĸ߶Ȳîh=0.8 m£»gÈ¡10 m/s2£¬sin53¡ã=0.8£¬cos53¡ã=0.6¡£Çó£º
£¨1£©Ð¡º¢×öƽÅ×Ô˶¯µÄ³õËٶȣ»
£¨2£©Ð¡º¢Ô˶¯µ½Ô²»¡¹ìµÀ×îµÍµãOʱ£¬¶Ô¹ìµÀµÄѹÁ¦¡£
£¨1£©ÓÉƽÅ×ÔÚÊúÖ±·½ÏòÊÇ×ÔÓÉÂäÌåÔ˶¯µÃ£º
¼´
ÓÉËÙ¶ÈÈý½ÇÐÎÓÐ
¼´£ºV0=m/s=3m/s
£¨2£©ÓÉ¿ªÊ¼µ½OµãÖ»ÓÐÖØÁ¦×ö¹¦ Óɶ¯Äܶ¨Àí
mg[h+R(1-cos)=mv2-mv02
ÔÚOµãÓÃÅ£¶ÙµÚ¶þ¶¨ÂÉÓÐ
N-mg=mv2/R
¼´£ºN= mg+mv2/R=¡¡=1290N
Á·Ï°²áϵÁдð°¸
Ïà¹ØÌâÄ¿