B Is Normal Force a Contact Force Despite Atomic Repulsion?

[Physics4Eva]

Guys I was just wondering if normal force is a contact force. Obviously it is considered a contact force but it also has something to do with the repelling of atoms. In my mind, normal force is a fundamental truth, but technically, are two objects touching or is there a minuscule space between the object.

 

[Dale]

Guys I was just wondering if normal force is a contact force.

Yes.

are two objects touching or is there a minuscule space between the object

If they are close enough for contact forces to exist then they are “touching”. It may be that contact forces have some small non zero range.

 

[Physics4Eva]

Thanks for the quick reply

 

[PhanthomJay]

Normal forces, and other so-called contact forces like tension and friction forces, belong to the family of forces called electro-magnetic forces (as distinguished from the strong and weak nuclear forces, and the ‘action at a distance’ classical gravity “force”). Being an electromagnetic force, contact forces actually never touch each other on the atomic scale, due to the repulsion of electrons between the objects in contact. For all practical purposes however, they can be considered as touching on the macroscopic scale.

 

[Physics4Eva]

Very intuitive

 

[A.T.]

... but technically, are two objects touching ...

What is your "technical" definition of touching?