Force on the current

[starbaduk]

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So, magnetic field can create a force on a current. But doesn't an external positive charge also apply force on the current?

From TBR Physics:

When a glass rod is rubbed with silk, it becomes positively charged. If it is held near the following objects, the rubbed glass rod may attract:

I. anything that is negatively charged
II. a magnetic compass
III. a current carrying wire.

Answer: I only

I thought since current is movement of electrons, an external charge would attract/repel a current-carrying wire. Is it because the current carrying wire has no net charge (maybe)?

 

[linkin06]

the wire would produce magnetic fields. but to have a force on a charge, the charge would have to be moving as well. F = qvxB, meaning the charge needs velocity.

 

[starbaduk]

Hey linkin06,

Yea, there would be no magnetic force without a moving charge. But I was wondering if there would be any electro "static" attraction between a static charge and a moving charge.

 

[Bernoull]

Hey linkin06,

Yea, there would be no magnetic force without a moving charge. But I was wondering if there would be any electro "static" attraction between a static charge and a moving charge.

Electrostatically, ur assuming that the the wire has a net charge, I am not convinced of that. I don't see any reason why #protons is not equal to # of electrons within any wire segment.. you clearly have electron drift velocity so u can have momentary dipoles which are incredible weak!!
Besides such thinking is way beyond what's reasonable for the question asked. So no net charge on wire so electrostatically, ur remaining possibility (for da wire) is induced dipoles courtesy of the approaching glass rod. Again induced dipoles are weak and the rod has to be pretty close to have any respectful attractive force. At those distances, magnetic force from the current in wire RULES, furthermore the magnetic force can NEVER point towards the wire, it points parallel to the wire and thus the wire and rod don't attract...