Magnetic flux on a surface

  • #1
Along a wire (of radius r) a current i is crossed from one.
Calculate the magnetic flux through the surface S, inner to the wire.

http://img138.imageshack.us/my.php?image=cilindrodb4.jpg

I think

[tex]\phi_b= \int B dS= BS[/tex]

[tex]B=\mu_0 i/2\pi r[/tex]

How to calculate S if I have not the length of wire?

The solution of the problem is
[tex]\phi_b=\mu_0 i /4\pi[/tex]
 
Last edited:

Answers and Replies

  • #2
Astronuc
Staff Emeritus
Science Advisor
18,869
2,134
If this is a wire 'loop' of radius r, then the length is simply 2[itex]\pi[/itex]r, and the area circumscribed by a circle is given by A = [itex]\pi[/itex]r2.
 
  • #3
Area=S

S is a rectangular (see image linked) surface, it is not a circle.

S would be the Area of a rectangular of base R and height=length of wire (infinite)
 

Related Threads on Magnetic flux on a surface

Replies
4
Views
1K
Replies
2
Views
1K
  • Last Post
Replies
5
Views
9K
  • Last Post
Replies
1
Views
3K
  • Last Post
Replies
4
Views
2K
  • Last Post
Replies
3
Views
3K
  • Last Post
Replies
2
Views
2K
  • Last Post
Replies
7
Views
1K
  • Last Post
Replies
13
Views
3K
  • Last Post
Replies
1
Views
814
Top