Induced current from changing magnetic field

Click For Summary
SUMMARY

The discussion focuses on calculating induced current from a changing magnetic field using the formula for electromotive force (emf). The key equations include emf = -d(Ф)/dt and Ф = B (dot) A, where B is defined as μi/(4πR). The solution involves integrating to find the total magnetic flux (φ) through the loop, noting that only the current (i) changes over time while area (A) and radius (R) remain constant.

PREREQUISITES
  • Understanding of electromagnetism principles, specifically Faraday's Law of Induction.
  • Familiarity with calculus, particularly differentiation and integration.
  • Knowledge of magnetic fields and their representation in physics.
  • Basic concepts of electric circuits and current flow.
NEXT STEPS
  • Study the derivation of Faraday's Law of Induction in detail.
  • Learn about the relationship between magnetic fields and electric currents in circuits.
  • Explore integration techniques for calculating total magnetic flux in varying conditions.
  • Investigate practical applications of induced current in electrical engineering.
USEFUL FOR

Students in physics, electrical engineers, and anyone interested in understanding the principles of electromagnetism and induced currents in circuits.

iharuyuki
Messages
15
Reaction score
1

Homework Statement


upload_2015-4-15_10-54-23.png


Homework Equations


emf = i (induced) R
emf = - d(Ф)/dt
Ф = B (dot) A
B = μi/(4piR)

The Attempt at a Solution



emf = - d(Ф)/dt
emf = - d( B (dot) A )/dt
emf = - d[ (μi/(4piR) * A ]/dt, A and B are perpendicular


Really not sure how to proceed from here as there are multiple derivatives (di/dt dR/dt and dA/dt) that I don't quite get.

Thank you very much.
 
Physics news on Phys.org
You have to calculate the total flux φ through the loop. Since B is a function of R, you have to integrate to find the total flux, which will be a function of i. In terms of your question about time derivatives, the only thing changing with time is i. A and R are constant in time.
 
Got it! Thank you very much.
 

Similar threads

Replies
8
Views
2K
Replies
11
Views
3K
  • · Replies 3 ·
Replies
3
Views
3K
Replies
4
Views
1K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 16 ·
Replies
16
Views
1K
  • · Replies 2 ·
Replies
2
Views
1K
Replies
11
Views
2K
Replies
12
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K