Also, for two surfaces, the coefficient of static friction is almost  always more than the coefficient of kinetic friction.

此外，对于两个表面，静摩擦系数几乎总是大于动摩擦系数。

You also happen to know that the coefficient of static friction between the box and the ramp is 0.50.

你也意识到摩擦的程度 盒子和斜坡之间的静态是 0。50。

And the maximum force of static friction is just equal to the coefficient of static friction times the normal force.

最大静摩擦力为 静摩擦力乘以法向力的程度。

The equation then is the force of static  friction is less than or equal to the coefficient of static friction times the force normal.

那么方程就是静摩擦力小于或等于静摩擦系数乘以法向力。

The maximum force of static friction which would prevent an object from sliding  on a surface is the force of static friction maximum equals the coefficient of static friction  times the force normal.

阻止物体在表面滑动的最大静摩擦力是静摩擦力最大值等于静摩擦系数乘以法向力。