Uniform Electrical potential energy

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SUMMARY

The discussion centers on the behavior of potential energy (PE) in a uniform electric field, specifically how it transitions from higher to lower potential energy as a point charge moves. The key equation involved is PE = qΔxE, where q represents charge, Δx is the change in position, and E is the electric field strength. It is established that while potential energy decreases as the particle accelerates towards lower potential energy, the concept of potential energy itself does not "move"; rather, it is the particle that experiences a change in kinetic energy due to the electrostatic force, F = qE. The conversation emphasizes the distinction between the movement of the particle and the static nature of potential energy.

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  • Understanding of electrostatics and electric fields
  • Familiarity with the concepts of potential energy and kinetic energy
  • Knowledge of conservative forces and work-energy principles
  • Basic proficiency in calculus for understanding derivatives in force equations
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Students of physics, electrical engineers, and educators seeking to deepen their understanding of electrostatics and the principles governing potential energy in electric fields.

ysmin55555
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Can someone explain the math of how potential energy travels from higher potential energy to lower potential energy (PE) along a uniform electric field?

I understand that in order for the point charge to move, gaining kinetic energy, it will lose potential energy. But using the equation PE=qdeltaXE, Q is positive, delta X is position and E is positive. So what am I missing to quantitatively show that potential energy is decreasing?
 
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ysmin55555 said:
delta X is position
##\Delta x## is change in position, which is negative in your example.
 
Your question can be more general. In one dimension:
the work done is dW = F Δx.
If the force is conservative, the potential energy is defined as ΔU = - ΔW = - F Δx
The force is F = - ΔU/Δx
So the force is in the direction of decreasing potential energy. That only says that the acceleration is in the direction of decreasing potential energy, not that the particle moves in the direction of decreasing potential energy. For example, the particle could be given an initial velocity in the direction of increasing potential energy (you could throw a ball up), and it would slow down because the force is opposite to the direction of motion.
The electrostatic force is a particular example of this, with F = qE.
 
ysmin55555 said:
how potential energy travels from higher potential energy to lower potential energy
That's not the way to discuss energy, imo. A system / object may move m(or just change) in such a way as to reduce the Potential Energy but the PE hasn't actually moved. A possible exception to that statement could be throwing a coiled spring across a room. In that case you could say that the PE of the coiled spring has moved but I don't think that would take you anywhere useful.
 
There was that problem in the language of ysmin55555. As sophiecentaur says, the potential energy does not move anywhere. It is the particle that accelerates towards lower potential energy.
 

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