Fundamental Forces

[akashgenius]

i hav a problem... As i understand it, there are 4 fundamental forces. now, these have been given various levels of strength. eg-you could say that gravity is the weakest force. however, when you talk about strength, there just isn't any way to compare their strengths. if we take gravity and electromagnetism, for example, gravity depends on the mass of 2 (say) particles, and electromagnetism would depend on the charge on 2 particles. so how is it possible to compare these forces when you have no possible relation between mass and charge? i mean to say that- since we have not yet found a link between the fundamental forces, we cannot compare them.

if x unit charge attracts a -x unit charge with some force, you cannot say that it is stronger than the force exerted between y-unit--y-unit particles. the mass and charge are totally different things. similarly, the force of gravity between me and the computer is more than that between a quark in the computer and a quark in my body, yet strong interaction is the strongest force. so just how can anyone compare these forces? it's like saying that water is heavier than iron because the weight of the ocean is more than the weight of an iron nail. or is there some other meaning for strength here? can someone pls help me out?

[Klaynos]

i hav a problem... As i understand it, there are 4 fundamental forces. now, these have been given various levels of strength. eg-you could say that gravity is the weakest force. however, when you talk about strength, there just isn't any way to compare their strengths. if we take gravity and electromagnetism, for example, gravity depends on the mass of 2 (say) particles, and electromagnetism would depend on the charge on 2 particles. so how is it possible to compare these forces when you have no possible relation between mass and charge? i mean to say that- since we have not yet found a link between the fundamental forces, we cannot compare them.

if x unit charge attracts a -x unit charge with some force, you cannot say that it is stronger than the force exerted between y-unit--y-unit particles. the mass and charge are totally different things. similarly, the force of gravity between me and the computer is more than that between a quark in the computer and a quark in my body, yet strong interaction is the strongest force. so just how can anyone compare these forces? it's like saying that water is heavier than iron because the weight of the ocean is more than the weight of an iron nail. or is there some other meaning for strength here? can someone pls help me out?

 

Well there's two ways I can think of, we can take force/unit, so for gravity that would be force/KG, for EM it would be force/eV etc... Or we can compare the strength of the forces between two particles at the distence we are interested in. Distance (and shielding) makes a very big difference for the fundemental forces.

[swansont]

i hav a problem... As i understand it, there are 4 fundamental forces. now, these have been given various levels of strength. eg-you could say that gravity is the weakest force. however, when you talk about strength, there just isn't any way to compare their strengths. if we take gravity and electromagnetism, for example, gravity depends on the mass of 2 (say) particles, and electromagnetism would depend on the charge on 2 particles. so how is it possible to compare these forces when you have no possible relation between mass and charge? i mean to say that- since we have not yet found a link between the fundamental forces, we cannot compare them.

if x unit charge attracts a -x unit charge with some force, you cannot say that it is stronger than the force exerted between y-unit--y-unit particles. the mass and charge are totally different things. similarly, the force of gravity between me and the computer is more than that between a quark in the computer and a quark in my body, yet strong interaction is the strongest force. so just how can anyone compare these forces? it's like saying that water is heavier than iron because the weight of the ocean is more than the weight of an iron nail. or is there some other meaning for strength here? can someone pls help me out?

 

Since all matter with which we are familiar is made up of neutrons, protons and electrons, it doesn't seem unreasonable to me to use the proton (or maybe deuteron) as the characteristic mass for comparison.

[akashgenius]

That still dosen't actually relate the fundamental forces- i mean, if we assume units such as N/gm or N/eV, sure it gives us a way to compare the forces per unit but that dosent throw any light upon the strength of the force. grams and electronvolts are completely unrelated units, you can't possible compare them. and besides- even if you do assume a characteristic particle for comparison, the nature of your deductions depend entirely on the properties of the particle, not on the forces themselves. it isn't possible to compare the forces unless you can link them to each other. and as to comparing their force at a fixed distance, that's it, the measurements of the forces will be unique only to that distance and does not shed anything on their so-called strength. i mean, at a distance of 100 m i can say that the force of gravity is strong than the strong nuclear force. it just dosent make sense to say that the strength of an electric current is stronger than the gravity of the earth. they're two completely unrelated things.