Register to reply

Induced charge in conductor

by mishima
Tags: charge, conductor, induced
Share this thread:
mishima
#1
Nov28-12, 08:41 PM
P: 335
Say you had a rectangular piece of conductor perfectly balanced on a central pivot point. Around it, you put something that causes an electric field throughout the region. On one end of the balanced piece, atomic cores get exposed as the electron sea rushes to the opposite side via induction. So would the piece now turn on the pivot, since one side was heavier than the other (one side has more electrons than the other)? Or does the force on the electrons somehow keep it up and oriented in the same direction despite weight differences?

I know this would probably never be able to be done in real life because of how small the mass is, I'm just wondering.
Phys.Org News Partner Physics news on Phys.org
Scientists uncover clues to role of magnetism in iron-based superconductors
Researchers find first direct evidence of 'spin symmetry' in atoms
X-ray laser probes tiny quantum tornadoes in superfluid droplets
Simon Bridge
#2
Nov28-12, 11:04 PM
Homework
Sci Advisor
HW Helper
Thanks
Simon Bridge's Avatar
P: 12,787
Lets tidy up to make this easier to think about:

You have a conducting beam which is initially balanced and you apply an external uniform electric field horizontally along the length of the beam. This causes a shift in the distribution of electrons to one side of the beam - which would shift the center of mass of the beam away from the pivot point and so it should tip up.

That seems reasonable.
You could imagine a negatively charged pivot and a non-conducting beam with a positive charged slug constrained to move along it's length. In this case you can construct a free-body diagram for the situation ... there would be a force ##qE## from the field, another ##kq^2/x^2## back along the beam, then there is gravity ##mg## acting down.

Have fun.

A version of this experiment has been done in real life - famously, by Millikan - using oil droplets in free-fall instead of a charged slug on a beam.


Register to reply

Related Discussions
If a conductor gets an induced charge is then grounded.. General Physics 2
Total induced charge of an infinite cylindrical conductor Advanced Physics Homework 9
Induced charge on a grounded conductor Advanced Physics Homework 4
Surface charge induced in conductor by point charge Introductory Physics Homework 17
Charge induced on conductor Classical Physics 0