The message to which you are about to reply is shown first. GO TO REPLY FORM



 VIEW    REPLY TO THIS MESSAGE Replies to this message will be emailed.    PRINT   SAVE 

More on electromagnetic fields in V70. S60, S80

posted by  serban on  Mon Feb 25 04:51 CST 2002
Author: [PROFILE] [EVERY POST] [THREADS] [BEST POSTS] RSS Feed     [IGNORE ALL POSTS] [RELATED]

Hi Claude,

your son is right, sorry for the mistake (I'm a computer scientist so physics was only course material for me). I looked at the fourth Maxwell's equation on electromagnetism and indeed, a magnetic field (B) depends on (the first derivative of) the electric field (E), and the

current_intensity * permeability_of_free_space.

This leads to something called Ampere's law that (after integration) shows:

permeability_of_free_space * I
B = -------------------------------
2 * PI * R

(B) is the magnetic field generated by the current (I) on a circle perpendicular on I, with radius (R).

Assuming
R = 1 meter
I = 1 Ampere
permeability_of_free_space = 4*PI*10_to_(-7)

we see that B = 2 * 10_to_(-7) Tesla (using MKS)

comparing this to the value of the earth magnetic field (~0.5 * 10_to_(-4))it seems that (B)in the car is relatively smaller (hundreds of times). However, a magnetic field also generates an electic field (E), as stated in the second Maxwell's equation. To compute (E) in the car is harder and I can't remember it on top of my head.

Sorry again,
Serban

PS. The numbers I derived for (B) are based on some assumptions, and may be different than what we really have in the car. How different? Don't know.





USERNAME
Use "claim to be" below if you don't want to log in.
PASSWORD
I don't have an account. Sign me up.
CLAIM TO BE
Use only if you don't want to login (post anonymously).
ENTER CAPTCHA CODE
This is required for posting anonymously.
OPTIONS notify by email
Available only to user accounts.
SUBJECT
MODEL/YEAR
MESSAGE

DICTIONARY
LABEL(S) +
IMAGE URL *
[IMAGE LIBRARY (UPLOAD/SELECT)]

* = Field is optional.

+ = Enter space delimited labels for this post. An example entry: 240 muffler


©Jarrod Stenberg 1997-2022. All material except where indicated.


All participants agree to these terms.

Brickboard.com is not affiliated with nor sponsored by AB Volvo, Volvo Car Corporation, Volvo Cars of North America, Inc. or Ford Motor Company. Brickboard.com is a Volvo owner/enthusiast site, similar to a club, and does not intend to pose as an official Volvo site. The official Volvo site can be found here.