The potential energy of two atoms-

AI Thread Summary
The potential energy of two atoms is expressed as U(r) = -4Uo[(Ro/r)^12 - (Ro/r)^6, and stable equilibrium is found by setting the force F(r) = -dU(r)/dr to zero. To find the work required to separate the atoms, one must calculate the potential energy at the equilibrium position and at infinite separation. The work done in separating the atoms is the difference between these two potential energy values. Understanding these concepts is crucial for solving the problem effectively.
noleguy33
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Homework Statement



The potential energy of two atoms with a radius r is written as-

U(r)= -4Uo[(Ro/r)^12 -(Ro/r)^6]

Find the radius at stable equilibrium and the work required to separate the two atoms.


Homework Equations



F(r) = -dU(r)/dr

The Attempt at a Solution



If found the stable equilibrium using the F(r) equation and setting it to zero. I have NO idea how to find the work.

A nudge in the right direction would be nice.
 
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You've worked out r at the equilibrium position.

So you can work out U at that position. I presume you're given U0, you can't get a numerical answer without it though you could get a simple symbolic expression.

U is a potential energy. Separating means moving them to infinite distance apart. The potential energy in that situation according to your formula is pretty obvious. The work separating is the difference between these two potential energies.

I trust I'm not teaching you anything but reminding you. (It seems so obvious you make me wonder if I'm missing something.)
 
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