Charged basketball, inertia ball and field

AI Thread Summary
The discussion revolves around the relationship between the charge of a basketball and its inertia due to the electrostatic field energy. It is clarified that charge alone does not equate to energy; rather, a charge in an electric field possesses electric potential energy. The concept of equating electrostatic energy with mass using E=mc^2 is challenged, as photons can have energy and momentum without mass. Additionally, the mass of the basketball can change with the addition or removal of electrons, but this does not directly correlate with the electrostatic field's energy. Ultimately, the electric field intensity around a charged ball represents a different aspect than energy, emphasizing the distinction between electric potential energy and the mass-energy equivalence principle.
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I was wondering how much I would have to charge a basket ball of mass M, so that I would begin to feel the inertia of the electrostatic field energy. We can calculate the total electrostatic field energy surrounding the charged basket ball, call it E. Can we then equate this energy E with a mass by E = mc^2? So that when the electrostatic energy surrounding the charged basket ball divided by the speed of light squared is a significant fraction of the mass of the basket ball we would notice the basket ball being harder to accelerate then an uncharged basket ball of mass M?

Edit, at the same time that we begin to notice the inertia of the electrostatic field would we also notice the charged ball was harder to spin?

Thanks!
 
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Charge by itself does not equate to energy. If a charge is present in an electric field, then you can say that the charge has electric potential energy, because the electric field has the potential to move the charge (much like a mass has gravitational potential energy, in a gravitational field).

As far as "relativistic mass equivalent" behaving as you describe, I am uncertain, but I am pretty sure that is not the way it works. Photons have energy and can have momentum, yet they are massless.
While adding charge can actually change the mass. Adding electrons to create net negative charge, and taking away electrons to create positive charge. Electrons do have a mass associated with them. Just something to think about.
 
E near a charged ball will represent ELectric Field Intensity which is not Energy. So it can't be equated in energy. E or V are just two different visualisations of behavior of space around a charge (Region is called Electric Field).

Energy here will be electric potential energy as scottdave said. But I'm not into relativity so can't figure out the last part.

Regards.
 
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