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Disclaimer: this question is really just for my own edification in preparation for a test.

In the figure above, we have a conducting bar that is placed onto two sloped conducting rails. The box labeled V is a voltage source. Lastly there is a magnetic field starting from the "base", rising up to the top of the plane of the computer screen. So basically the B field is perpendicular to the base, which is labeled in the figure.

My question pertained to Faraday and Lenz's Law. Say the bar is set at the very bottom of the bar at f-a.

My first question is: If there is a voltage applied between points a and f, why does bar begin to climb the slope? Eventually coming to rest at an elevated point?

My logic is as follows: the current created by the voltage opposes the external magnetic field, reducing its strength somehow. According to Lenz's law, this decrease in magnetic flux must be opposed by an induced magnetic field and induced current... so the conducting bar climbs the slope to create both the induced magnetic field and induced current. And it does so by rising up the slope, increasing the area. And using the right hand rule, the direction of the current induced by the rising conducting bar would be from a-->x-->y--> f? Is this logic correct?

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Disclaimer #2: The next question follows on the assumption that all of my logic above the dotted line is correct...

My second question is: which direction is the current (initiated by the voltage) going if the conducting bar is rising? My logic is that the current (initiated by the voltage) MUST be reducing the field strength, as I have explained above the dotted line. By using right-hand rule, this means that the current initiated by the voltage MUST be going from f --> y --> x --> a --> f.

Is this the correct direction and logic?

Thank you so much PF! I have been learning from yall for years! :) you guys never fail me :) this site is so helpful. I wish every subject had a site like this. Someday, I'm sure.

Disclaimer: this question is really just for my own edification in preparation for a test.

In the figure above, we have a conducting bar that is placed onto two sloped conducting rails. The box labeled V is a voltage source. Lastly there is a magnetic field starting from the "base", rising up to the top of the plane of the computer screen. So basically the B field is perpendicular to the base, which is labeled in the figure.

My question pertained to Faraday and Lenz's Law. Say the bar is set at the very bottom of the bar at f-a.

My first question is: If there is a voltage applied between points a and f, why does bar begin to climb the slope? Eventually coming to rest at an elevated point?

My logic is as follows: the current created by the voltage opposes the external magnetic field, reducing its strength somehow. According to Lenz's law, this decrease in magnetic flux must be opposed by an induced magnetic field and induced current... so the conducting bar climbs the slope to create both the induced magnetic field and induced current. And it does so by rising up the slope, increasing the area. And using the right hand rule, the direction of the current induced by the rising conducting bar would be from a-->x-->y--> f? Is this logic correct?

----------------------------------------------------------------------------------------------

Disclaimer #2: The next question follows on the assumption that all of my logic above the dotted line is correct...

My second question is: which direction is the current (initiated by the voltage) going if the conducting bar is rising? My logic is that the current (initiated by the voltage) MUST be reducing the field strength, as I have explained above the dotted line. By using right-hand rule, this means that the current initiated by the voltage MUST be going from f --> y --> x --> a --> f.

Is this the correct direction and logic?

Thank you so much PF! I have been learning from yall for years! :) you guys never fail me :) this site is so helpful. I wish every subject had a site like this. Someday, I'm sure.

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