Can someone explain to me force field strengths versus distance squared?

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SUMMARY

The discussion centers on the inverse square law as it applies to forces, specifically gravitational and electrostatic forces, represented by the equations F=Gm1m2/r² and F=kQ1Q2/r². Participants explain that the distance squared relationship is empirically validated, indicating that as distance from an object increases, the force diminishes by the square of that distance. This principle is observed in various natural phenomena, including light intensity and magnetic forces, highlighting the prevalence of non-linear relationships in physics.

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  • Understanding of basic physics concepts, particularly forces and fields.
  • Familiarity with mathematical functions, especially square and inverse functions.
  • Knowledge of gravitational and electrostatic force equations.
  • Basic comprehension of experimental measurement techniques in physics.
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  • Study the properties of inverse square laws in gravitational and electrostatic contexts.
  • Learn about linear and logarithmic functions to understand different types of relationships.
  • Investigate the behavior of magnetic forces and their distance dependencies.
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Hey guys, I'm wondering why is distance squared in these equations?

Like F=Gm1m1/r^2 and F=kQ1Q1/r^2

Thanks
 
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AliSkully said:
Hey guys, I'm wondering why is distance squared in these equations?

Like F=Gm1m1/r^2 and F=kQ1Q1/r^2

Thanks
Because when you measure those experimentally, that's what matches.

And beyond that, what is the realationship between the radius and surface area of a sphere? :smile:
 
Yes, the square function is just indicating that for every distance you move away or to the 'object' it is not directly or indirectly proportional but increases or decreases by the square of the distance.

It's the way nature is...Its physics!

For instance if you measure the power to a radio receiver at one distance then move back that same distance, or double the distance away, it will not be 1/2 as strong but but a squared law function. Like -2,-4,-16,-34 for the same increment of distance away.

A Lot of things are like that in nature. Light, gravity, forces, radio wave strengths, tidal waves, even my voice level when I scream at students.

There are more functions than just linear functions. If you take 2 poles of a magnet that are 4 feet apart and measure the attractive force, like berkman suggested, then moved the 2 magnets 2 feet apart the strength would not have doubled but would have gone up by a factor of 4 times and so on...

I would suggest that you study linear functions (step), logarithmic functions (exponential) and then the square functions, to name a few.

After you do, tell us what kind of function a coil spring exhibits pushing or pulling the same increments of length, the answer might surprise you!
 
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