Register to reply

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

by sachin123
Tags: h-field, magnetic field stren
Share this thread:
sachin123
#1
Feb20-11, 12:03 AM
P: 121
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
Phys.Org News Partner Science news on Phys.org
Security CTO to detail Android Fake ID flaw at Black Hat
Huge waves measured for first time in Arctic Ocean
Mysterious molecules in space
tiny-tim
#2
Feb20-11, 10:41 AM
Sci Advisor
HW Helper
Thanks
tiny-tim's Avatar
P: 26,157
hi sachin123!

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

(and "strength" just means "amount"
you can leave it out when writing, and ignore it when reading )
sachin123
#3
Feb20-11, 01:34 PM
P: 121
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)

tiny-tim
#4
Feb20-11, 02:14 PM
Sci Advisor
HW Helper
Thanks
tiny-tim's Avatar
P: 26,157
Difference between Electric flux density,electric field strength....

Quote Quote by sachin123 View Post
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

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 )
sachin123
#5
Feb20-11, 02:52 PM
P: 121
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?
sachin123
#6
Feb20-11, 09:47 PM
P: 121
'mu' i meant as [tex]\mu[/tex]


Register to reply

Related Discussions
Parallel Plate Capacitor: Electric field strength, flux & magnetic field Introductory Physics Homework 0
Flux of an Electric field with a constant charge density Advanced Physics Homework 5
Electric Flux Density / Electric Field Intensity Classical Physics 1
Potential difference to find the magnitude of the electric field strength Introductory Physics Homework 2
Calculating electric field from radiant flux density Introductory Physics Homework 1