What is the energy conversion if you shoot a gun?

Answer 1

In a gun, the energy is initially stored as chemical energy in the gunpowder. When it is fired, this energy is converted to several different forms. First, it is converted into thermal energy. This causes gasses to expand behind the bullet, and so a portion of this thermal energy is converted to the kinetic energy of the bullet. Some of the bullet's energy is converted to heat by friction in the barrel on the way out. The rest of the thermal energy remains as heat in the hot gasses, or in the barrel. A small amount of chemical energy remains unused also, in the form of unburned gunpowder. Some of the energy is also converted to sound waves, creating the bang. Here is the energy conversion breakdown for a typical small firearm:

• Projectile motion 32%
• Barrel friction 2%
• Hot gases 34%
• Barrel heat 30%
• Unburned propellant 1%
• Sound energy <1%