Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: rocking_1987 on 05/08/2012 04:09:22

Title: why do we need extreme amount of energy to breakdown the atom?
Post by: rocking_1987 on 05/08/2012 04:09:22

Hi,

Its make sense that we need more force to break bigger things and less force to break small things. I mean you will need more force to break truck than car.

Even in the atom you may break the atom using much less energy then why do we need extreme energy to break the particles? (for example to collide them at the speed of the light)

What makes them so strong? If they are so much strong as an individual then why atom itself is breakable at much less energy?

Do we have to use the speed just because we don't have any equipment which can hit them directly? What's the reason behind using the speed to break them?

Title: Re: why do we need extreme amount of energy to breakdown the atom?
Post by: evan_au on 05/08/2012 06:06:53

Scientists know of 4 fundamental forces in the universe:

• Gravity: Extremely weak - the gravitational attraction between two atoms is almost nothing
• Electromagnetism: The attraction between electrons and protons. It is enough to hold atoms together in molecules, solids & liquids. Because it is so strong, a spark quickly discharges any large excess positive or negative charge, leaving only gravity at large distances.
• Strong Nuclear Force: About 100 times stronger than electromagnetism, it holds protons & neutrons together in the nucleus despite the protons positive charge repelling each other very strongly. Only has a very short range (within the nucleus of the atom).
• Weak Nuclear Force: Governs some rare interactions including neutrinos. Extremely short range, and about a million times weaker than the strong nuclear force.

The electrons of an atom provide an electric force field which will repel any negatively charged particle, and the protons of the nucleus provide an electric force field which will repel any positively charged particle.

So to produce nuclear reactions in a controlled way, we need very high energies which will overcome the electric force, to get close enough to the nucleus to interact via the strong nuclear force.

To provide a fast enough rate of interactions which use the weak nuclear force, we need enough energy to produce W & Z bosons at about 90 GeV energy.
http://en.wikipedia.org/wiki/Weak_interaction#Properties