|MadSci Network: Physics|
Hi Suzy, You're question is very intriguing. Often when one thinks of simple fundamentals in detail, one comes up with very refreshing insights. Let us go into the atomic level and see what happens. At the atomic level all the atoms have their share of electrons. So everything is in the “Un-excited” state. Ie: More or less things are dormant. When an electron enters this region the following may take place. 1. No atoms might attract the electron. In that case the electron will drift across the conductor and get out at the other end. (Do keep in mind that whenever you apply a voltage across a conductor, thousands of electrons enter the conductor pushing those in front of them further away from their source.) 2. An atom may take in that electron into its orbit. This will cause an instability in the atom and the atom might develop a negative charge. This however cannot last for long and the atom will release it. The electron might then go into another atom and keep shifting from atom to atom till it reaches the other end. In reality both of the above may happen. The electron may enter a few atoms and skim over the others. The second part of your question is whether the exact same electron would be thrown out at the other end. This may not be the case in most cases. When the atom releases the electron there is a possibility that it releases a different electron than what it took in. However, all electrons are exactly identical, so there is no way of practically confirming if the electron that goes in, is the electron that comes out. If that sounds a little confusing, let me explain it in a slightly different way: Imagine a glass filled to the brim with water. Now what happens if you add one more drop. Another drop exits the glass from the periphery. Whether it’s the same drop or not is difficult to tell. That depends on where the drop entered. Secondly, all the drops look alike. Now let the glass be the conductor, and the water be the electrons. Get the picture!! Cheers, Nauzad Tantra
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