Which Rule is Correct for Determining the Direction of Lorentz Force?

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Homework Help Overview

The discussion revolves around the correct application of the left-hand and right-hand rules for determining the direction of the Lorentz force in the context of magnetic fields and charged particles. Participants are exploring the nuances of these rules and their applicability in different scenarios.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants are comparing the left-hand and right-hand rules, questioning their correctness and applicability for the Lorentz force. Some express confusion about the roles of fingers in each rule and seek to clarify the definitions and setups involved.

Discussion Status

The discussion is active, with participants sharing their learned interpretations of the rules and expressing differing views on their correctness. Some guidance has been offered regarding the use of the right-hand rule, but no consensus has been reached on which rule is definitively correct.

Contextual Notes

There is mention of conventional current and the distinction between positive and negative charges, which may influence the understanding of the rules. Participants are also reflecting on their educational backgrounds and how they learned these concepts.

physicsmaths1613
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Generally we use the left hand rule - (if index finger shows velocity, middle finger shows magnetic field, the thumb points towards force). Recently I also came across a left hand rule for lorentz force- Using your right-hand: point your index finger in the direction of the charge's velocity, v, (recall conventional current). Point your middle finger in the direction of the magnetic field, B.

Your thumb now points in the direction of the magnetic force. Generally left hand rule is used for determining the direction of induced current in a conductor placed in a magnetic field. Are both of these rules given above correct?Can we use any of them for determining the direction of lorentz force?
 
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Are both of these rules given above correct?
... why don't you compare them and see?
 
physicsmaths1613 said:
Generally we use the left hand rule - (if index finger shows velocity, middle finger shows magnetic field, the thumb points towards force). Recently I also came across a left hand rule for lorentz force- Using your right-hand: point your index finger in the direction of the charge's velocity, v, (recall conventional current). Point your middle finger in the direction of the magnetic field, B.

Your thumb now points in the direction of the magnetic force. Generally left hand rule is used for determining the direction of induced current in a conductor placed in a magnetic field. Are both of these rules given above correct?Can we use any of them for determining the direction of lorentz force?
I would stick with the right-hand rule and let the signs take care of phenomena such as the direction of induced current in a conductor placed in a magnetic field.
 
physicsmaths1613 said:
Generally we use the left hand rule - (if index finger shows velocity, middle finger shows magnetic field, the thumb points towards force). Recently I also came across a left hand rule for lorentz force- Using your right-hand: point your index finger in the direction of the charge's velocity, v, (recall conventional current). Point your middle finger in the direction of the magnetic field, B.

Your thumb now points in the direction of the magnetic force. Generally left hand rule is used for determining the direction of induced current in a conductor placed in a magnetic field. Are both of these rules given above correct?Can we use any of them for determining the direction of lorentz force?

I think this is wrong !
First finger is field, middle finger is velocity and thumb is force...I may be wrong !
 
This is how I learned it for deflection of a wire in a magnetic field...
First finger is the Field
Second finger is the Current
Thumb is the movement

So for force on a charge, current is the same direction as the velocity of a positive charge (reverse for negative charges)
The thumb becomes the force.
 
Simon Bridge said:
This is how I learned it for deflection of a wire in a magnetic field...
First finger is the Field
Second finger is the Current
Thumb is the movement

So for force on a charge, current is the same direction as the velocity of a positive charge (reverse for negative charges)
The thumb becomes the force.

I agree..I was not wrong
 

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