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Touching

Question:

When we touch any substance then we touch it's molecules. So, do we touch electrons revolving around nucleus? I got one answer as follows: "Touching" is electric repulsion between atoms on surface. If it is true, then will you explain this effect?


Answer:

Strictly speaking in Physics nothing ever "touches". The effect of one object on another is due to an electromagnetic force producing an action at a distance. As the two objects involved get closer together even down to molecular levels the force gets bigger.

There is a very good graph to show this in many books (and on the schoolphysics.co.uk web site), it shows the force varying from a very large repulsive value when two molecules are close and then becoming attractive as they are pulled apart past the equilibrium position finally dropping of to effectively zero at infinite separation.

Also try looking up Van der Waals forces.

So you don't actually touch the electrons moving round the nucleus, the electrons and nuclei in your finger produce a field of their own which repels the field produced by the object that you are touching. Don't worry your electrons will not get tangled up with the electrons of the object.

It is actually a very complex topic involving quantum Physics but I hope that I have said enough to help you.


 
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© Keith Gibbs 2016