Force in field? Why isn't it constant?

In summary, distance is a key variable in fields such as gravitational, electric, and magnetic fields. However, as the distance increases, the force decreases substantially. This is because the strength of the field falls off as the square of the distance, which is essential for the existence of atoms and living beings. While the force may appear to be constant around the field, it actually varies at different distances and approaches zero at larger distances. This behavior is determined by the equations governing the fields, which are based on experimental data and fundamental theories.
  • #1
Wiz700
96
1
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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  • #2
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 :tongue:). 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.
 
  • #3
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.
 
  • #4
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.
 
  • #5


I can explain the concept of force in fields and why it is not constant. Force is a physical quantity that describes the interaction between two objects. In the case of fields, force refers to the influence that a source object has on another object in its surrounding space.

In fields such as gravitational, electric, and magnetic fields, the force experienced by an object is dependent on the distance between the source object and the affected object. This means that as the distance increases, the force decreases.

The reason for this is due to the nature of fields themselves. Fields are created by sources, such as a planet for gravitational fields or a magnet for magnetic fields. These sources have a certain amount of energy or strength, which is spread out in all directions, forming a field. As the distance from the source increases, the energy or strength of the field decreases, resulting in a decrease in force experienced by the affected object.

Additionally, in fields such as the gravitational field of a planet, the force experienced by an object also depends on the mass of the source object. As the distance increases, the force decreases, but the mass of the source object also plays a role in determining the strength of the force.

So, why can't the force be constant all around the field? This is because fields are not uniform in nature. They can vary in strength and direction at different points in space. This is why the force experienced by an object also varies with distance in a field. The force is strongest when the object is closest to the source and decreases as the distance increases.

In conclusion, the force in fields is not constant because of the nature of fields themselves. As the distance from the source increases, the strength of the field decreases, resulting in a decrease in force experienced by the affected object. This is a fundamental concept in the study of fields and is essential for understanding the interactions between objects in our universe.
 

1. What is "force in field"?

"Force in field" refers to the influence that a field, such as a gravitational or electric field, has on an object. It is the force that is exerted on an object at a particular point in space due to the presence of the field.

2. How is force in field measured?

Force in field is typically measured in units of Newtons (N) using a tool called a force meter or a spring scale. The force meter measures the amount of force that is being applied to an object in a specific direction.

3. Why does force in field change in different locations?

Force in field is not constant because the strength of a field can vary based on the distance from the source of the field. For example, the force of gravity on an object will be stronger closer to the Earth's surface compared to further away from it.

4. How does mass affect force in field?

The greater the mass of an object, the greater the force in field will be. This is because the mass of an object determines how much it will be affected by the force of the field. For example, a heavier object will experience a stronger gravitational force than a lighter object.

5. Can force in field be negative?

Yes, force in field can be negative. This occurs when the force is acting in the opposite direction to the direction of the field. For example, if an object is moving against the direction of a gravitational field, the force in field will be negative.

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