Difference between Electric flux density,electric field strength .

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sachin123
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Difference between Electric flux density,electric field strength...

I want to know the difference between,electric flux density and electric field strength.Are they the same?
And also,there is a magnetic field(measured in Tesla),magnetic flux(in Weber),magnetic flux density(Weber per m2),magnetic field strength(measured in Tesla again?).
I am finding these very confusing.Can someone clear this out?
Thanks
 
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hi sachin123! :smile:

from the pf library on flux …
In electromagnetism, flux always means total flow through a surface (a scalar), and is measured in webers (magnetic flux) or volt-metres (electric flux).

Flux is the amount of a vector field going through a surface: it is the integral (over the surface) of the normal component of the field​

flux density (btw, this is density per area, not per volume) is the same as the field …

flux = ∫ field "dot" area, so field = flux per area = flux density …

tesla = weber/metre2 :wink:

(and "strength" just means "amount" …

you can leave it out when writing, and ignore it when reading :wink:)​
 


I am clear with Electric field strength(=electric flux density) and electric flux.

1.)Does it mean that magnetic field strength=magnetic flux density?

and...
from what you said,
magnetic field strength = magnetic field.But,here is what my book says:
Magnetic field strength (H)=B/[tex]\mu[/tex]
where B is magnetic flux density.
Now weren't they supposed to be the same?(magnetic flux density and Magnetic field strength)
 
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sachin123 said:
But,here is what my book says:
Magnetic field strength (H)=B/[tex]\mu[/tex]
where B is magnetic flux density.
Now weren't they supposed to be the same?(magnetic flux density and Magnetic field strength)

ah, i see …

your book is calling H (in amps per metre) the magnetic field strength …

i haven't come across that before …

i've seen magnetic field intensity for H, but not strength :redface:

oh, in that case forget what i said about ignoring the word "strength": clearly some books are using it to distinguish H from B (in webers per metre squared)

(but the best way to distinguish them is to call them the H-field and the B-field :wink:)
 


So,to conclude it,

magnetic flux is number of magnetic lines passing through surface area...
unit:weber

magnetic flux density is number of magnetic lines passing through unit surface area...
unit:weber per (m square)

magnetic field is same as magnetic flux density

magnetic field strength =magnetic field intensity is H =B/(mu)
unit:A per m

Is it correct?:smile:
 
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'mu' i meant as [tex]\mu[/tex]