To streatch a certain nonlinear spring by an amount 2x requires a force F given by F=40x-6x^2 where F is in newtons and x is in meters. What is the change in potential energy when the spring is stretched 2 meters from its equilibrium position?
a)16 J
b)28 J
c)56 J
d)64 J
e)80 J
P.E. = mgh but how would I relate this to this current problem? Or would the answer just be c) 56 J ( I got this by plugging in 2 for x in the equation)
PE= INT F dx
integrated F dx from zero to 2m.