ããéç¨æ´ä½å弧æ³åææ¶ï¼æ¤æ³è®¤ä¸ºæ»å¨åä½ç»åå¿åç转å¨ï¼å
¶æåä½ä½ä¸ºåä½è¿è¡åæï¼åä½çéå产çä¸æ»åç©ï¼åçç²èååéåçåå产çææ»åç©ï¼ææ»åç©åä¸æ»åç©çæ¯å¼ä¸ºåå¡ç稳å®
å®å
¨ç³»æ°ãåªéç¨äº=0çæ
åµã
ããæ¡åæ³æ¯å设æ»å¨é¢ä¸ºä¸å弧é¢ï¼å°åä½å为è¥å¹²åæ¡ï¼è®¾æ¯ä¸ªåæ¡ä¸ºåä½ï¼æ±åºæ¯ä¸æ¡çææ»åãåç©åä¸æ»åãåç©ï¼ä¸åçæ¡åæ³æä¸åçå
¬å¼æ±æ»å¨åä½ç稳å®å®å
¨ç³»æ°ã