# Is energy stored in velcro considered Elastic Potential Energy in an inelastic Collision?

So just some background for the question, if two pucks with velcro on each side on very slippery ice with close to no friction collide, they stick together. Thus, the collision is inelastic.

However, I'm confused as to where the lost kinetic energy goes? People have said sound and thermal energy (from friction), but since there are velcro pieces on each side of both pucks I'm wondering if some of the energy is stored in the velcro as elastic potential energy?

Basically, I'm not sure what to call the energy stored in the velcro (if any is even stored in the velcro) because it's not exactly deformed from the collision, it just sticks with the other velcro piece.

Anyway if someone could clarify 1. Where the kinetic energy goes and 2. If it does go to the velcro, what kind of energy is it and how does it "affect" the velcro, that would be very much appreciated :)

("affect" being like how kinetic energy increases the speed of an object, or thermal energy raises its temperature, or how elastic potential energy in a spring compresses or stretches it).

• Various part of the velcro pads will end in a strained configuration, but it's disordered and I presume relatively little energy in the grand scheme of things. Apr 8, 2018 at 21:52
• I wonder if energy is stored by the fact that the velcro is sticking together? Apr 8, 2018 at 21:56
• Energy can be stored via the elastic strain in an object (as mediated by its stiffness), but I don't really see how the hook-and-loop closures in velcro after a collision are deformed in any way that's significantly different from how they were deformed before the collision. Apr 8, 2018 at 23:01