normal force是不是支持力啊?

就是和一个平面垂直的力.
Normal force翻译过来是正向力,你也可以叫它支持力.但是支持力可能不是单方向,其中和平面垂直的component才是normal force.
"In mechanics,the normal force Fn is the component,perpendicular to the surface of contact,of the contact force exerted on an object by,for example,the surface of a floor or wall,preventing the object from penetrating the surface."

物理上叫法向力或正交力