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

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The discussion centers on the correct application of the left-hand and right-hand rules for determining the direction of the Lorentz force. The left-hand rule is traditionally used for induced current in a magnetic field, while the right-hand rule is suggested for determining the magnetic force on a charge. Participants debate the correct orientation of fingers in these rules, with some asserting that the right-hand rule is preferable for clarity in understanding the Lorentz force. Confusion arises over the roles of velocity, magnetic field, and force in each rule. Ultimately, the consensus leans towards the right-hand rule for accurately determining the Lorentz force direction.
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
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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