As we know that here gun + bullet system is isolated from all other external force system
so here the momentum of system is always conserved
so we will say
here we know that
now we will have
by solving above equation we will have
When a match stick is struck, some of the chemical energy is transformed into heat and light and the rest is converted into matter. A match stick has a lot of chemical energy stored in it. When its struck, It start burning. The chemical energy stored in it is transformed into heat energy and light energy. The rest of it turn into ashes and reaction gases.
Most probably physical, even though the change of liquids to solids is directly related to chemistry too
