• Support PF! Buy your school textbooks, materials and every day products Here!

Average induced EMF

  • Thread starter matt72lsu
  • Start date
  • #1
94
0

Homework Statement



The area of a 100 turn coil oriented with its plane perpendicular to a 0.28 T magnetic field is 4.3×10−2 m^2.
Find the average induced emf in this coil if the magnetic field reverses its direction in 0.36 s.

Homework Equations



E = -N (flux - flux initial)/(t-to)

The Attempt at a Solution


I'm actually not even sure I am using the correct equation. It is the only one I see that uses N. But I'm not sure how I would find an initial time and even a flux. Help?
 

Answers and Replies

  • #2
kuruman
Science Advisor
Homework Helper
Insights Author
Gold Member
8,586
2,031
It is the correct formula.
Look up the definition of flux.
Note that the denominator is t - t0. How does "... reverses its direction in 0.36 s" relate to t - t0?
 
  • #3
94
0
ok i found something in which i can use BAcostheta instead of flux... would that work? and i guess t would be 36 and initial would be zero?
 
  • #4
kuruman
Science Advisor
Homework Helper
Insights Author
Gold Member
8,586
2,031
Correct on both accounts. What is cos(theta) here?
 
  • #5
94
0
is it just 1?
 
  • #6
94
0
also would A stay the same? and how to find B? or do you have to find B initial?
 
  • #7
kuruman
Science Advisor
Homework Helper
Insights Author
Gold Member
8,586
2,031
is it just 1?
Yes.
also would A stay the same? and how to find B? or do you have to find B initial?
A stays the same. As for B, read the problem carefully; Binitial and Bfinal are both given to you.
 

Related Threads for: Average induced EMF

Replies
8
Views
21K
  • Last Post
Replies
1
Views
5K
  • Last Post
Replies
5
Views
772
  • Last Post
Replies
10
Views
934
  • Last Post
Replies
2
Views
3K
Replies
1
Views
8K
Replies
2
Views
2K
Top