Spring constant of a bent pvc pipe

[snocavotia]

I am calculating the initial velocity of a released pvc pipe after it has been bent. I would like to know if i have this correct.

Potential energy = Kmgh; I have my mg and it is 50N, so PE = k*50*h;

I have been told that k is the spring constant of my bent pvc pipe. Therefore since I have 50N already i can say that k = -50/h. h is my displacement so I am going to say for experiment's sake that my displacement is 10m. therefore my spring constant is -5N/m.

So now we can say PE = (-5)*50*10(once again 10 is my displacement).

Does this mean that my potential energy is 2,500J? Also is my spring constant correct?

 

[SteamKing]

Has your pipe really been bent 10 meters? That's about the height of a three-story building.

How long is this pipe? Is it fixed at one end with the other end deflected?

 

[snocavotia]

Haha that was a rhetorical length. My real length will be about .4 meters. And my displacement will probably be .5 or .6. And there is an axel through the other end. It is bent over a triangle shaped crossbeam.