哈哈,曲率半径处处相等,摩擦系数点点为零.

来源: 吴用先生于 2010-05-17 18:28:44 [博客] [旧帖] [给我悄悄话] 本文已被阅读：次

WENXUECITY.COM does not represent or guarantee the truthfulness, accuracy, or reliability of any of communications posted by other users.