Decreasing Energy due to attraction

[Subham Roni]

Why does the energy of a system decrease when two charged particles attract each other?

[daniton]

Its actually about Book - keeping. It is the definition(agreement) of Energy.

do you why the potential energy of an object decrease as its height from earth decrease.

[cresol]

it really depends on the system

[studiot]

I am not sure what you mean by this question.

 

Do you mean the potential energy?

 

Do you mean that the potential energy is different for two particles that have no charge and two that do?

 

Do you mean the potential or total or kinetic energy changes if two charged particles mocve towards each other?

 

or What?

[Subham Roni]

Ok I am being specific why I asked the question.

Electrons have negative energy values. At infinite distance(out of boundary of atom) the electron is considered to have no energy at all as it isn't attracted by the protons. I understood this.

But as it moves closer to the nucleus, it is attracted by the protons and energy is released and energy of system decreases. Why?

[swansont]

Ok I am being specific why I asked the question.

 

Electrons have negative energy values. At infinite distance(out of boundary of atom) the electron is considered to have no energy at all as it isn't attracted by the protons. I understood this.

But as it moves closer to the nucleus, it is attracted by the protons and energy is released and energy of system decreases. Why?

 

It depends on what "why" represents.

 

Energy is released, as you say. If you release energy, the energy you have goes down. That's how we balance the books: energy is conserved.

 

Another way of answering is: the force is attractive. The energy involved is the work; the incremental work is defined as dW = Fdx. Since the force is attractive the work is negative. As the electron approaches the proton the potential energy decreases (the work) but since energy is conserved, the kinetic energy increases. In atoms, though, there is the release of a photon, which is reduction of the energy of the system.

[Subham Roni]

OKie.. Got it..
I wanted the 2nd answer! This forum is awesome!
Bookmarked it!