Electric potential at the center of a dipole

AI Thread Summary
The electric potential at the center of an electric dipole is zero, which raises questions about the work required to bring a charge from infinity to this point. When a charge is placed along the horizontal bisector of the dipole, it experiences a force that is always perpendicular to its motion, meaning no work is done against this force. This explains why the total work required to move a test charge to the center of the dipole remains zero. Understanding this concept clarifies the apparent contradiction regarding work and electric potential in dipoles. The discussion effectively resolves confusion about the nature of electric forces and potential in dipole configurations.
kavan
Messages
5
Reaction score
0
Potential at the center of an electric dipole is zero. This doesn't make intuitive sense, how can work required to bring an arbitrary charge from infinity to the center of a dipole be zero? Imagine a charge at some distance on horizontal bisector of the dipole, it will deflect from the horizontal line and get attracted to one or the other dipole charge...that means there will be some nonzero work involved to bring test charge to the center of the dipole. Can anyone please throw some light on it?
 
Physics news on Phys.org
kavan said:
Imagine a charge at some distance on horizontal bisector of the dipole, it will deflect from the horizontal line and get attracted to one or the other dipole charge...that means there will be some nonzero work involved to bring test charge to the center of the dipole.

No. If the particle moves along the bisector line, the electric force on it is always perpendicular to the direction of motion. Therefore the force that you exert on the charge to counteract the electric force and keep the charge from straying from the line, does no work.
 
Oh...got it. Thanks a lot, i was stuck with it for quite some time.
 
I was using the Smith chart to determine the input impedance of a transmission line that has a reflection from the load. One can do this if one knows the characteristic impedance Zo, the degree of mismatch of the load ZL and the length of the transmission line in wavelengths. However, my question is: Consider the input impedance of a wave which appears back at the source after reflection from the load and has traveled for some fraction of a wavelength. The impedance of this wave as it...
Back
Top