force;非接觸力,作用力,反作用力

它們的大小(相同)
它們的方向(相同)
它們是施加在(同一)的物體上

3種力系一齊發生

In the actual fact, the term "non-contact" is applied in the macroscopic sense. Most, if not all, of the "contact forces" observed in the macroscopic world are electromagentic in nature, such as friction, pushing force on a block, collision force... etc.. They arises because of the electromagnetic interaction of molecules on the objects in contact.

我想問non-contract force系吾系得兩隻?
正系得magnetic force&force of gravity?
If you limit yourself to observation in the macroscopic world, non-contact forces include gravitational force and electromagentic force (i.e. electric and magnetic forces)

如果推一樣野
咁摩擦力,作用力同反作用力有無關系?
The action forc is just the force you applied to push an object, whereas the reaction force is the force acting on you (i.e. the resistance force that you feel). They are separated from frictional force.

系指尼3種力系咪一齊發生?
Yes.