Direction of induced current in the loop

AI Thread Summary
The discussion centers on understanding the direction of induced current in a loop due to a moving electron. The participant conceptualizes the moving electron as an infinitesimal current element, which shifts its position as it moves. They reference the Biot-Savart law to explain how the magnetic field's magnitude changes as the electron moves, leading to a reversal in the direction of EMF and induced current. The response confirms that this reasoning is adequate for introductory physics, validating the treatment of the moving electron as a tiny current element. Overall, the explanation effectively addresses the relationship between moving charges and induced currents.
Jahnavi
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Homework Statement


electron-induced current.png


Homework Equations

The Attempt at a Solution



I am having a little doubt as to how to think of the moving electron as a current .

I am considering the moving electron as a very tiny (infinitesimal ) current element . It is as if when the electron is at A , there is a very tiny current element at A . As electron moves from A to B , this small current element also shifts it's position continuously from A to B .

From Biot - Savart law , we see that the magnetic field depends on the distance . As the distance first decreases and then increases, the magnitude of magnetic field through the loop first increases , then decreases .The direction of EMF and induced current reverses direction .Option 4) is correct .

Is my reasoning correct ? More importantly is it correct to treat moving electron as a tiny current element which continuously changes its position ?
 

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Jahnavi said:
Is my reasoning correct ? More importantly is it correct to treat moving electron as a tiny current element which continuously changes its position ?
See here for the correct treatment of a moving charge and the fields it generates.
https://en.wikipedia.org/wiki/Liénard–Wiechert_potential
For the purposes of answering the multiple choice question in an introductory physics context, your reasoning is good enough.
 
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