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Name: Unknown
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: Around 1993
Question:
How do you explain picking up a penny with Aluminum Foil?

I was shown a demonstration the other day that mystified me. A man could pick up small pieces of aluminum foil with a penny by just touching the two together. There was no adhesive on either surface. What was the force that was lifting the foil? I cannot find any reference to similar experiments anywhere. Any ideas?


Replies:
This is an educated guess: Aluminum and copper have different numbers of electrons and have the highest filled energy level at different energies. This means that if you put the two metals together the electrons will move from one to the other because electrons can lower their energy by filling lower energy levels. This does not continue forever since the electrons leave positive charges on the metal they have left. When the metal is charged up enough the electrons stop moving and then we have two materials with opposite charges and these charges will attract, hence the force of attraction.

Sam Bowen


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