What does U represent in U=1/2*k*x²?

[Grinter1]

I don't understand what U is?
Is It to do with hookes law?
Is it to do with kinetic energy?


U=1/2*k*x^2

 

[uart]

It is energy stored in a spring, with spring constant "k", compressed or extended by an amount "x" from it's equilibrium length.

 

[Fightfish]

U usually refers to potential energy (or some particular form of it).
Indeed, this equation is somewhat linked to Hooke's Law; it gives the elastic potential energy stored in a spring when the spring has been compressed or extended by a distance x. k, in this case, is the spring constant of the spring.