Well, it is sticking straight out, but sticking straight out in a slightly different way from what happens with a sphere. See, the sides of a cylinder are vertical.
它垂直于其表面指向外面，但这与球面法向量的指向的方式有点不同，圆柱的边缘是竖直的。
3
Unlike the better balanced straight-six or even the ultra-smooth V-12 engine, the humble four-cylinder generates an up and down vibration with a frequency of twice the crankshaft's rotational speed.