Confused on the Electrical Energy Formula?

AI Thread Summary
The discussion clarifies the application of the electrical energy formula Ee = k(q1)(q2)/r, addressing confusion about potential energy between charges. When a positive and negative charge are very close (r=0.00001m), the formula indicates a large negative potential energy, reflecting that energy is required to separate them. Conversely, when two positive charges are far apart (r=1000), the energy is expected to be small, as it requires energy to overcome their repulsion. The concept of negative energy is explained as counterintuitive but important for understanding energy differences in a potential field. Overall, the key takeaway is that potential energy varies significantly based on the distance and nature of the charges involved.
012anonymousx
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This is probably a silly question.

The Electrical energy formula is this:
Ee = k(q1)(q2)/r

So let's say a positive and negative charge are directly next to each other.
Conceptually, there should be no potential energy there.
But the formula (r=0.00001m) suggests that it is huge.

On the other end, if two positive charges are far away from each other (r=1000), energy should be huge, but the formula suggests it gets smaller.

I appreciate all the help!
 
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012anonymousx said:
But the formula (r=0.00001m) suggests that it is huge.

Actually, it says it should be hugely negative, as q1q2 is negative. Bringing them apart (increasing r) should increase the potential energy, which makes sense, as it takes energy to move them apart. (Note that the concept of negative energy might seem counterintuitive at first, but, by gauge symmetry, the only thing we care about is the difference between two energies in a potential field.)

On the other end, if two positive charges are far away from each other (r=1000), energy should be huge, but the formula suggests it gets smaller.

On the contrary, the energy should be tiny, as you have to pour in some energy to overcome the force repelling the charges.
 
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