I'm reading through an ENM text called Introduction to Electrodynamics by Griffiths, and in the section on work and energy, after giving the expression for work, he says:
"That's how much work it takes to assemble a configuration of point charges; it's also the amount of work you'd get back if you dismantled the system. In the meantime, it represents energy stored in the configuration ("potential" energy, if you insist, though for obvious reasons I prefer to avoid that word in this context.)
Those reasons aren't so obvious to me, lol. Why does Griffiths want to avoid the term "potential energy"? Seems to me like it makes sense, assembling point charges is analogous to holding a rock a few feet off the ground – there's energy stored in both, when released the rock falls down a gravitational gradient and when "released", a charge would "fall down" an electric gradient. What nuances am I missing here?
Best Answer
Because electric potential and potential energy are two different things.They are related ofcourse but they are different.(check page number 80).
You may be thinking that
"Electric potential energy of a charged object at a point is the amount of work done to bring that object from infinity to that point
and electric potential at a point is just amount of work done needed to bring an object with unit charge to that point from infinity .So potential energy and potential are nearly same thing".
This is correct but not always .It is only correct when the reference point is at infinity.
$$\text{Electric potential} =\dfrac{\text{electric potential energy}}{\text{charge}} $$
This equation is only true when the reference point is at infinity . But electric potential and potential energy in general are different things really.
So to avoid confusion call potential energy ,the electrostatic energy .