Insights Blog
-- Browse All Articles --
Physics Articles
Physics Tutorials
Physics Guides
Physics FAQ
Math Articles
Math Tutorials
Math Guides
Math FAQ
Education Articles
Education Guides
Bio/Chem Articles
Technology Guides
Computer Science Tutorials
Forums
Classical Physics
Quantum Physics
Quantum Interpretations
Special and General Relativity
Atomic and Condensed Matter
Nuclear and Particle Physics
Beyond the Standard Model
Cosmology
Astronomy and Astrophysics
Other Physics Topics
Trending
Featured Threads
Log in
Register
What's new
Search
Search
Search titles only
By:
Classical Physics
Quantum Physics
Quantum Interpretations
Special and General Relativity
Atomic and Condensed Matter
Nuclear and Particle Physics
Beyond the Standard Model
Cosmology
Astronomy and Astrophysics
Other Physics Topics
Menu
Log in
Register
Navigation
More options
Contact us
Close Menu
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Forums
Physics
Other Physics Topics
Field strength variation of different types of fields
Reply to thread
Message
[QUOTE="BiGyElLoWhAt, post: 5516438, member: 496972"] I think it comes from conservation of energy. If you look at the point source of a field, it will generate a field out radially. Try to imagine a charge being created. It gets created, and the field propagates out radially, making a spherical wave front with area 4 pi r^2. The energy on that surface should be the same as the energy at a previous surface, or any later surface, since if it were to annihilate, it will have "generated" a finite amount of energy, that energy will continue to propagate in the same direction (barring strong gravitational fields and the like). This means the energy density must decrease. If we compare the total energy of some small area, call it ##\Delta A## at some small value of r, we will find it to be rather high. Now if we move to larger r, but keep the same ##\Delta A## we'll find it to be lower. Requiring the total energy through the surface at ##r_1## to be the same as that of ##r_2##, we get that ##E_1 = E_2## and ##\rho_1 *4\pi r_1^2 = \rho_2 *4\pi r_2^2## and ##\frac{\rho_1}{\rho_2} = \frac{r_2^2}{r_1^2}## which is a form of the inverse square law. So ##\rho_1 \propto \frac{1}{r_1^2}## It literally just comes from the fact that a spheres surface area is proportional to r^2. Fermions do have rest mass, at least all of the ones I'm aware of. Electrons, protons, etc. It's worth noting that the same logic can be applied to any radially propagating conserved quantity. [/QUOTE]
Insert quotes…
Post reply
Forums
Physics
Other Physics Topics
Field strength variation of different types of fields
Back
Top