U(x)=x12a−x6bU(x=∞)=0 as, F=−dxdU=−[x1312a+x76 b] at equilibrium, F=0 ∴∴∴x6=b2aUat equiltrium =(b2a)2a−(b2a)b=4a−b2D=[U(x=∞)−Uat equilibium ]=4ab2
JEE Main 2010 — Physics Mechanics
The potential energy function for the force between two atoms in a diatomic molecule is approximately given by U(x)=x12a−x6b, where a and b are constants and x is the distance between the atoms. If the dissociation energy of the molecule is D=[U(x=∞)−Uat equilbrium ],D is
Held on 30 Apr 2010 · Verified 6 Jul 2026.
2ab2
12ab2
4ab2
6ab2
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