Assuming I had a magic device able to discharge its stored energy in a directional force, and absorb the energy from the resulting return force (for every action, there is an equal and opposite reaction) which it could then discharge... What laws of physics are being violated? (basically, energy that would have moved the device, ignoring obstacles like ground, instead just gets stored as magic. This device can freely exchange between kinetic and magic energy, so 1KE absorbed is 1KE of discharge. And it is selective in what it converts to magic, so it is affected by gravity, it does not absorb that).
Looking at it from conservation of energy, this would be 100% efficient energy transfer (from kinetic, to magic to kinetic) so the device should have no power left after the discharge, but since there is energy in the return force... is there no return force or is the return force a fraction of the discharge force? If the later, what is that fraction?
The device just converts kinetic energy, to magic, to kinetic energy with 100% effecency. I just want a reality check on how this device works given that the energy absorb/discharge is the only exception to physics happening.
Just as an example, you charge the device by striking it with a hammer, than place a ball bearing next to the device (physically touching it), the device than discharges its energy into the ball as kinetic energy, and stores the recoil energy from the ball, which can than be used to launch another ball bearing. What would be the speed of each ball bearing? (assuming whatever makes the math easier/cleaner and doesn't violate physics)