A force can be a push or a pull ... Similarly, a stiletto heel creates far more pressure than a normal shoe. A person wearing a stiletto can exert more pressure on the ground than an army tank!
When an object pushes on a surface like a table, wall or the ground, the surface pushes back on the object with a balancing force. The normal reaction force always acts at right angles to the surface.
一些您可能无法访问的结果已被隐去。
显示无法访问的结果