在什么表面上球滚的最快

来源：百度知道 编辑：UC知道 时间：2024/05/26 21:20:24
回答有英文的!!!!!!!!!!!急,明天要交!!!!!!!!!!!(on what surface did a ball roll fastest?)

斜面

on a frictional inclined surface whose coefficient of kinetic friction(u) satisfies u=（2/7）×tan（a）, where a denotes the inclined angle of the surface.
The underlying principle is to make the ball rotate without sliding.
A--linear acceleration along the surface
linear motion: mgsina-umgcosa=mA
rotation: 2/5mr^2 * b = umgcosa * r (r--radius of the solid sphere, b--angular acceleration)
non-sliding condition a=b*r
solve the above 3 equations and get u=（2/7）×tan（a）

the surface without friction没有摩擦力的表面
或者 or
bevel 斜面

The surface without friction没有摩擦力的表面