例1直线的曲率处处为零 △a=0,K △O\=0 △ 例2圆上各点处的曲率等于半径的倒数,且 半径越小曲率越大 设圆的半径为,△s=a·△a △a △a1 K △s 上一页下一页返回例1 直线的曲率处处为零. 例2 圆上各点处的曲率等于半径的倒数,且 半径越小曲率越大. 0, = 0    = = s K   s a 1 =   设圆的半径为a,s = a s a K 1 =   = 