Force in field? Why isn't it constant?

AI Thread Summary
Distance significantly impacts the strength of gravitational, electric, and magnetic fields, with force decreasing as distance increases, typically following an inverse square law. This variation in force is essential for the stability of physical systems, as a constant force would disrupt fundamental interactions. While some fields can exhibit uniform strength under specific conditions, most do not, and their behavior is dictated by governing equations derived from experimental data. The diminishing force at large distances approaches zero but is never truly zero. Understanding these principles is crucial for grasping the nature of fields and their effects on matter.
Wiz700
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Distance is a key variable with fields, however, why is it, in any field(Gravitational,Electric,Magnetic) as "d" increase, F decrease substantially?

Why can't the force x, be constant all around the field. Amazingly, the force is different at each value of d, well in most cases its zero when d is a large number.
 
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Wiz700 said:
Distance is a key variable with fields, however, why is it, in any field(Gravitational,Electric,Magnetic) as "d" increase, F decrease substantially?

Why can't the force x, be constant all around the field.

Because its not. Why would you want it to be that way, anyway? The falling off of the strength of the field as the square of the distance is literally what makes the world go round. Atoms wouldn't exist, tissue wouldn't exist, WE wouldn't exist. (I'm starting to sound like a discovery show commentator now :-p). Try building a computer simulation of your suggested universe and see how things turn out once you hit "run." Then you'll know why the 1/r^2 law is fine just the way it is.

Amazingly, the force is different at each value of d, well in most cases its zero when d is a large number.

Well, technically, it is never zero, but it does get vanishingly small pretty fast.
 
You are thinking of specific field configurations (the Newtonian field, Coulomb field, and magnetic field due to a current wire respectively). The electric field due to an infinite charged plane is uniform, the gravitational field within the Earth is approximately uniform, the magnetic field within an infinitely long current solenoid is uniform etc.
 
Well...DiracPool and WannabeNewton mentioned good points...but I think I still can add sth.
As the last post says,not all fields have the same spatial behavior...and for everyone of them,you can ask why it is like this...and for all of them,there is only one answer:because of the equations governing the fields! And more or less,those equations are determined by experimental data and more fundamental theories.
 
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