The potential energy between two atoms in a molecule is given by `U(x)= (a)/(x^(12))-(b)/(x^(6))`, where a and b are positive constants and x is the distance between the atoms. The atom is in stable equilibrium when

Options

A. `x = 0`
B. `x = (a//2b)^(1//6)`
C. `x = (2a//b)^(1//6)`
D. `x = (11a//5b)^(1//6)`

Answer

c

Explanation

For stable equilibrium `du//dx = 0-12a//x^(13) = -6b//x^(7) = 0, x = (2a//b)^(1//6)`