Electromagnetic induction with a moving loop When a closed conducting loop is moved through a magnetic field, what occurs regarding induced voltage, current, and polarity?

Difficulty: Easy

Correct Answer: All of the above

Explanation:


Introduction / Context:
Faraday’s law and Lenz’s law govern electromagnetic induction: motion of a conductor in a magnetic field produces an electromotive force (EMF). If the conductor forms a closed loop, this EMF drives a current whose direction opposes the change that created it. Understanding these principles is fundamental to generators, inductive sensors, and eddy-current braking.


Given Data / Assumptions:

  • Closed wire loop (complete circuit).
  • Uniform magnetic field intersecting the loop area.
  • Finite motion causing change in magnetic flux linkage.


Concept / Approach:
Faraday’s law: induced EMF magnitude is proportional to the rate of change of flux linkage. Lenz’s law: induced current direction opposes the flux change. Polarity therefore depends on whether the loop enters or leaves the field and on the direction of motion relative to the field lines.


Step-by-Step Solution:
Move loop so that flux through it changes → EMF appears across the loop.Because loop is closed, EMF drives an induced current.Reverse motion or flip field orientation → polarity reverses accordingly.Thus, all three statements (voltage induced, current induced, polarity depends on motion) are correct.


Verification / Alternative check:
Generator action: rotating coils in a magnetic field produce AC because polarity alternates as the coil turns, perfectly illustrating motion-dependent polarity.


Why Other Options Are Wrong:
Choosing only one statement ignores the complete behavior of EMF, current, and motion-dependent polarity.


Common Pitfalls:
Assuming motion is required even when flux changes due to time-varying fields can also induce EMF; both relative motion and time-varying fields work by changing flux linkage.


Final Answer:
All of the above

More Questions from Magnetism and Electromagnetism

Discussion & Comments

No comments yet. Be the first to comment!
Join Discussion