I was first introduced to this concept in a movie entitled What the Bleep? Down the Rabbit Hole which I would highly recommend to anybody with the slightest interested in physics, or a curiosity to find out something new about the world. Basically, one part of the movie claimed that no two objects ever actually come into physical contact with each other in the real world. One might immediately say something like, "Then how come I can feel something when my hand gets close enough to it?"

The answer is that when you get close to an object, what you are actually feeling is the force created by the repulsion between the electrons in your hand (or other body part) and the electrons of that object. Different objects give you a different sensation because their unique chemical composition and physical structure causes varying amounts of forces (in the repulsion between your electrons and the electrons of that object).

The example given in the movie specifically refers to the bouncing of a basketball on a basketball court. You initially give the ball a downward velocity (which over time increases due to gravitational acceleration) and send it falling towards the concrete (or whatever substance the court floor is made of). As the ball starts approaching the floor, there is a slight repulsion between its electrons and those of the floor. As the ball gets closer, the force of repulsion becomes greater and greater (to keep the approaching ball's electrons from ever coming into physical contact with the floor's electrons). Eventually, this force becomes so great that it 'bounces' the ball back up towards you.

I just found it very interesting to imagine that at this moment, as I type on my keyboard, I am not actually touching the keys. The force of repulsion given off by the electrons on my fingertips is simply greater than that given off by the keys, which is why I am able to force them down and type this post. Kind of makes you question some of your basic perceptions on the world when you find out that something you that was so obvious or knew so much about turns out to be completely different than you had originally thought.

 

 

 

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What you are saying is True.

Touching is the contact between two objects. And we cannot expect the electrons on the outer surface of one object being touched to the electrons of the other. This can actually cause a reaction and then might even result into electron exchange.

The force exerted by the electrons definitely gets affected by the velocity of the object into consideration. However, for a physical study and calculations, we consider the object as a whole and apply simple kinetic equations to get our answers (which tally with the real life readings).

To say in simple words, I know the monitor which I see this site does not understand anything and its all about series of 0's and 1's which are processed on a large scale by my processor. But, to make things simple, We have developed high level programming language for easy understanding and working with it.

-Shree

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True. It's actually real simple. It's High School science. That's exactly the reason why if we fall from a place we don't get sucked right into the core of the Earth but rather fall flat on the Earth's surface. Because Electro-magnetic force is far greater in strength than Gravitational force. The repulsion between the electrons of our skin/clothes and the Earth's surface is way too much for Gravity to overcome.

This was even shown in the "Elegant Universe" series. This thing applies to anything and everything as nothing is made-up of something other than atoms and molecules. Be it your keyboard, your body, your drum kit, the ball. Though it is kinda amazing that heat and friction, texture all still can be felt. The accurateness of the electrons! Something more amazing to imagine. You pluck the strings on your guitar, but it isn't actually your fingers that are pulling the string, it's the "wall of repulsion" between the string and your finger that's doing the task.

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