A point charge near a stream of water

AI Thread Summary
A point charge near a narrow stream of water will attract the water due to the water molecules being permanent electric dipoles. The electric field created by the point charge interacts with the dipoles, causing them to align and experience a net force towards the charge. While a uniform electric field can torque a dipole without moving it, a point charge generates a non-uniform field that can exert a pulling force. The discussion references the Maxwell stress tensor to explain the forces acting on dielectric bodies in an electric field. This principle is also applied in fluidic pumps that operate without moving parts.
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Homework Statement


if a point charge is brought near a narrow stream of water will the water be attracted to the charge, repelled from it, or neither? why? water molecules are permanent electric dipoles.


Homework Equations


not sure


The Attempt at a Solution


i don't think the water would be affected by the charge
 
Physics news on Phys.org
This comes up a lot.

A uniform electric field will torque but not pull or push a dipole. But a point charge doesn't have a uniform field, right?

Q: what are the forces on a dielectric body in an electric field? The answer has to do with the Maxwell stress tensor. Hint: there are US patents for fluidic pumps with no moving parts that are based on these principles.
 

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