Warning: file_put_contents(): Only 0 of 4993 bytes written, possibly out of free disk space in /www/wwwroot/ppbbu/cp667.com/index.php on line 55 coefficient of friction英英字典_coefficient of friction剑桥英语解释_coefficient of friction柯林斯英文解释_淳朴汉英词典
1. N the force required to move two sliding surfaces over each other, divided by the force holding them together. It is reduced once the motion has started 摩擦系數[mechanical engineering]