Magnetic flux against e.m.f (V)

  • Thread starter Googl
  • Start date
  • #1
111
1

Main Question or Discussion Point

Hi,

Could someone confirm for me please. As the magnetic flux increases does the e.m.f increase as well? (solenoid) And if we were to plot a graph of the two against each other, the graph will have a positive line/curve. My graph has a negative curve suggesting that as flux increases e.m.f decreases, that's wrong right?

Thanks.
 

Answers and Replies

  • #2
marcusl
Science Advisor
Gold Member
2,699
361
It depends on how you defined the positive and negative terminals of your solenoid relative to the field inside. Here's how to figure it out.

A changing magnetic flux [tex]\phi[/tex] produces a "back emf" [tex]\varepsilon[/tex] according to

[tex]\varepsilon=-\frac{d\phi}{dt}[/tex]

According to Lenz's Law, the sign of the emf is such as to produce a current that produces a flux that opposes the external change in flux.
 

Related Threads for: Magnetic flux against e.m.f (V)

  • Last Post
Replies
1
Views
769
Replies
5
Views
3K
  • Last Post
Replies
1
Views
2K
  • Last Post
Replies
3
Views
547
  • Last Post
Replies
3
Views
6K
Replies
2
Views
1K
  • Last Post
Replies
1
Views
589
Top