Answer :
Final answer:
The energy of a bullet is directly related to the rifle barrel length due to the longer acceleration distance provided by the barrel. As a result, a bullet fired from a 24-inch barrel will have more energy compared to one fired from a 16-inch barrel. Additionally, the term 'conserving energy' refers to the practice of reducing energy consumption, in contrast to the 'conservation of energy,' which is a fundamental principle in physics.
Explanation:
Understanding Bullet Energy and Barrel Length
The energy of a bullet is significantly influenced by the barrel length through which it is fired. For rifles with a 24-inch barrel, the PMC Bronze 147 grain and Speer Gold Dot 150 grain bullets will have certain energy levels. With a reduction in barrel length to 16 inches, the energy will indeed be less, due to a shorter distance for the gunpowder to expand and accelerate the bullet; in other words, less work is done on the bullet. This is largely due to the principles of physics related to barrel length and the kinetic energy imparted to a bullet.
Bullets leaving a rifle typically are traveling at a much higher velocity due to the longer barrel, which allows more time for the expanding gases from the gunpowder to act on the bullet, increasing its velocity and hence its kinetic energy. Kinetic energy is calculated using the formula ½mv², where 'm' is the mass and 'v' is the velocity of the bullet. A longer barrel typically means a higher velocity, thus a greater kinetic energy for the projectile.
With respect to conservation, there are two distinct concepts worth distinguishing. Conserving energy refers to practical measures taken to reduce energy consumption, such as turning off lights or lowering a thermostat. On the other hand, the law of conservation of energy in physics states that energy cannot be created or destroyed in an isolated system, only converted from one form to another.
