Question

The potential energy of an object attached to a spring whose elastic constant is k is given by the formula p e space equals space 1 half k x squared . the quantity x is the displacement from the equilibrium condition. assume that k = 25 n/m and x = 1,5 m: determine the pe.

Answer 1

You know the following:
k= 25N/m
x=1.5m
Now you just plug these numbers into the formula which is
Epe = 1/2kx²
       = 1/2(25N/m)(1.5m)²
       =  28.125J or in proper sigdigs 28J 
Hope this helps!