Direction of magnetic field in antenna

AI Thread Summary
The discussion centers on the direction of the magnetic field in an antenna, questioning whether it should be clockwise based on the current's downward direction. Participants clarify that current does not flow through empty space and that the flow of charge results in an increasingly positive charge in the upper rod while the lower rod's charge is drawn into the battery. The current in both rods ultimately diminishes to zero as the system reaches equilibrium. The explanation provided is appreciated for its clarity compared to the textbook's description. Understanding the flow of charge and its implications on current is crucial in this context.
sparkle123
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In the middle picture, since the current is directed downward (I think), by the right hand rule shouldn't the magnetic field lines be clockwise?
Thanks!
 
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'Positives' (conventional charge) looks like it is flowing up into the top element, and up out of the bottom element ('leaving behind' a -ve charge), just like the arrows show. No?
 
Thanks!
but the purple arrows I(t) are flowing down?
Also, I'm not sure if the current can flow down the conductors through empty space...
 
Hi sparkle123! :smile:

No the current does not flow through empty space.
The purple arrow from the plus pole continues its flow into the upper rod where it dead-ends, resulting in a increasingly positive charge.
In the upper rod the current flows up.

Similarly, charge from the lower rod is sucked into the battery, resulting in a current flowing up in the lower rod.

These flows cannot continue indefinitely, since the charge has nowhere else to go.
So soon after the current starts flowing, the current diminishes until it is zero.
 
Thanks I like Serena! :) That makes so much more sense!
I wish the textbook explained it the way you did - it just says that when the rods are fully charged, the current is zero.
 
Thanks! :blushing:
 
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