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Name: Matt J.
Status: student
Age: 15
Location: N/A
Country: N/A
Date: 9/22/2004

How do protons within the nucleus stay so tightly packed if they have the same charge?


The nucleus of atoms are held together by one of the four fundamental forces called The Strong Force. It is a very strong force but it acts over a very short range. It is an exchange force with exchange particles called pions and other heavy particles.

Bob Hartwell

Dear Matt,

The protons (and neutrons) in a nucleus are held together by the "strong force". This force is about 100 times stronger than the electromagnetic force which produces the repulsive force between objects with the same sign of charge. The range of the strong force, however, is very short -- about 1.0E-13m = 0.0000000000001 meters, which explains why all nuclei are this size or somewhat larger. The electromagnetic force has an infinite range, like gravity, though it falls off in strength rapidly as the charged particles get further apart.

This explains why nuclei became less stable and some decay as the number of protons in the nucleus increases, Uranium, which has 92 protons and 146 neutrons in its nucleus is the most massive nucleus which is stable. The fact that it is barely stable explains why it gives up energy when it splits into smaller and more stable nuclei and so can be used to generate electrical power and to make nuclear bombs.

Best, Dick Plano...

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