Ballistic trayectory/impact damage

[ZionCity]

Homework Statement

I don't know if this one belongs to something like the mythbusters, because of the complexity it needs for the actual testing.
This is the situation: in my country every week somebody gets hurt because of stray bullets, This is provoked by irresponsible people who tend to celebrate by firing guns into the air as if they don't realize that the bullets eventually come back down.

Usually the injuries occur when the bullets go true metal roofing and/or wood roofing.
The metal roofing material used in third world counties is usually corrugated galvanized tin leafs 2 meters long by 1 meter wide. 0.2 cm thick. the wood is usually 0.5' pine plywood (the one you USA's use for hurricane protection). The question here is what would be the final velocity of a 45 caliber bullet (most commonly used caliber in my country) fired from a (taurus, baretta) type hand gun. And if possible what would be the impact force at final velocity.

Let's say that the gun is fired at 90 degrees, 80, degrees, 75, degrees, and so on.

Homework Equations

the bullet waight is important and imagine a wind speed of maybe 10 m/h for the present wind.

The Attempt at a Solution

The answer to this problem might give us an idea on how many sheets of metal would be needed to prevent a stray bullet from going true and hurting people.

thanks.

 

[KataKoniK]

First of all, I want to say that it is very concerning to hear about the issue of stray bullets causing injuries in your country. It is important for people to understand the consequences of their actions and to act responsibly.

In terms of your question about the final velocity and impact force of a 45 caliber bullet fired from a handgun, there are a few factors that need to be considered. These include the initial velocity of the bullet, the angle at which it is fired, and the air resistance it experiences on its way up and down.

To accurately calculate the final velocity and impact force, we would need to conduct controlled experiments in a controlled environment. This would involve setting up a shooting range with different types of roofing materials and measuring the velocity and impact force of the bullet at different angles.

In general, the final velocity of a bullet fired at a 90 degree angle would be higher than at a lower angle, as there is less air resistance. However, the impact force would also be influenced by the angle and the type of material it is impacting.

I would recommend that measures be taken to prevent people from firing guns into the air, such as stricter laws and education about the dangers of stray bullets. In terms of using metal roofing as a protective measure, it is important to consider the thickness and quality of the metal, as well as its ability to withstand impact forces.

I hope this information helps and I urge everyone to act responsibly and prioritize the safety of others in their actions.
Scientist

 

[Mene]

it is important to address the issue of ballistic trajectory and impact damage caused by stray bullets. This is a serious problem that can result in injuries or even fatalities. The irresponsible use of firearms is a concern and it is necessary to understand the physics behind it in order to prevent such incidents from occurring.

To calculate the final velocity of a bullet fired from a handgun, we need to consider factors such as the muzzle velocity of the bullet, the angle at which it is fired, and the resistance of the materials it encounters. The muzzle velocity of a 45 caliber bullet can vary depending on the type of handgun and ammunition used, but it can range from 800 to 1000 feet per second (fps). For this calculation, let's assume a muzzle velocity of 900 fps.

The angle at which the bullet is fired also plays a crucial role in its trajectory. A bullet fired at a 90 degree angle (straight up) will reach its maximum height and then fall back down at the same speed, assuming no air resistance. However, as the angle decreases, the bullet will travel farther horizontally and will have a higher final velocity when it reaches the ground. For example, a bullet fired at a 45 degree angle will travel twice the distance of a bullet fired at a 90 degree angle, and will have a final velocity of approximately 800 fps when it hits the ground.

The resistance of the materials the bullet encounters will also affect its final velocity. In this case, the corrugated metal roofing and plywood are both relatively thin and lightweight materials, so they will not slow down the bullet significantly. However, if the bullet were to hit a thicker or denser material, such as a concrete wall, its final velocity would be much lower.

To calculate the impact force of the bullet, we need to consider its mass and final velocity. The weight of a 45 caliber bullet can range from 230 to 255 grains (0.52 to 0.58 ounces). Using the final velocity of 800 fps, we can calculate the kinetic energy of the bullet using the equation KE = 1/2 * m * v^2, where m is the mass of the bullet and v is the final velocity. This will give us the amount of energy the bullet has upon impact. However, it is important to note that the actual impact force will also depend on the surface area of the impact and the amount of time the force is applied.

In order