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

DescriptionThermal energy refers to several distinct thermodynamic quantities, such as the internal energy of a system; heat or sensible heat, which are defined as types of energy transfer; or for the characteristic energy of a degree of freedom in a thermal system, where is temperature and is the Boltzmann constant.
1.If a compound is made from a metal and a non-metal, its bonding will be ionic.
2.If a compound is made from two non-metals, its bonding will be covalent.