Does electric potential exist without a test charge?

AI Thread Summary
Electric potential can be defined independently of a test charge by using the formula for potential, which calculates the energy per unit charge at a point in space. While electric potential energy pertains to a system of two charges, potential itself represents the specific energy required to move a charge from infinity to that point. Thus, potential is not the energy of the entire system but rather the energy associated with a unit charge in the field created by the source charge. This distinction clarifies how potential can exist without directly referencing a test charge. Understanding this concept is crucial for analyzing electric fields and potentials effectively.
etotheipi
Usually for a charge Q we state that for each point in space there exists a potential, and we can calculate this, draw graphs of potential etc.

However, if electric potential energy is a property of a system of two charges, and potential is PE for a 1C test charge, then how can we even define a potential? Is it assumed that the potential at any point in space is the potential energy the system of the source charge and the test charge would have if the test charge were at that point?

Perhaps in a more general sense, is it more common to just talk about the potential energy of a particle in the field of the source particle as opposed to the two charge system?

Edit
I think I figured it out.. sorry for the null thread!
 
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etotheipi said:
then how can we even define a potential?
By using the formula for the potential. There, defined.
etotheipi said:
Is it assumed that the potential at any point in space is the potential energy the system of the source charge and the test charge would have if the test charge were at that point?
It is not the energy of the overall system. It is the specific energy (energy per charge) needed to bring a charge from very far away to that point.
 
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