I was thinking about a situation: In space there is our setup, a wood piece of mass $m$ and a coil and permanent magnet of mass $m$. The coil is placed a light second far from the magnet. The magnet is now given a force to move with a velocity $V$ (let's assume 100m/s).
After half of a second the magnet strikes with the wood block and loses all its velocity. All the kinetic energy of the magnet is gained by the wood (which is not a magnet).
But we know that the magnet was also releasing magnetic fields. And when it started moving, there was a changing strength of magnetic field produces that reaches the coil after 1sec (the coil was 1 light second far in space).
Is this not violating conservation of energy as all of the mechanical energy given to magnet (in the system) was gained by the wood. But due to the velocity of the magnetic field the magnetic field had not reached the coil in given time (before the magnet loses its K.E.), so they can't produce any of their own magnetic field caused by induced current and therefore can't affect the magnet in that given time.
But to add to this, when there is current induced in coil after 1 sec, it's magnetic field produced forces the magnet to move.
So we are only putting $mv^2/2$ energy which was transferred from magnet to the wood by collision but there comes extra output which is current induced in the coil and magnet's motion, why is it not a violation to law of Conservation of energy?