The Physics Behind a Bullet Hitting The Human Body

[MG5]

Ok so I'm trying to show how a bullet in real life will not actually make a person fly backwards like it does in movies. I have some idea of how to go about this but need help.

So far...

I know it's a perfectly inelastic collision since the bullet sticks into the person so would I have to use this? m₁v₁ + m₂v₂ = (m₁+m₂) v_2f

Or would I only be using momentum and/or force?

Bullet
m=.008kg
v= 430 m/s

Person

m=84kg

 

[Hypersphere]

I know it's a perfectly inelastic collision since the bullet sticks into the person so would I have to use this? m₁v₁ + m₂v₂ = (m₁+m₂) v_2f

Yes, you do have momentum conservation.

Or would I only be using momentum and/or force?

Sorry, what do you mean? The momentum is certainly imparted to the shot person through a force, but you don't know either the magnitude of the force or the duration of time it acts on the person, do you?

 

[MG5]

Yes, you do have momentum conservation.



Sorry, what do you mean? The momentum is certainly imparted to the shot person through a force, but you don't know either the magnitude of the force or the duration of time it acts on the person, do you?

No I don't know either of those values. Since I'm choosing a scene from a movie where this type of thing would happen, I'm not given any values. I just have to estimate the givens such as mass, velocity of bullet, mass of person and stuff like that and solve for everything else.

 

[Pkruse]

The momentum imparted to the victim will be less than that imparted to the shooter by the recoil of the gun. Did that knock him down?

I saw a training vidio once where they shot a guy wearing heavy body armor in the chest with several different high powered rifles, and a 12 ga deer slug. All this while he balanced on one foot. He just stood there and was not even close to falling down.

I've talked with several snipers, and with people who were standing next to people hit by a sniper, and I've read the witness accounts. A heart shot causes them to drop like someone turned off a switch. A brain shot causes them to thrash around randomly for a little while. Any motion by the victim after being shot other than simply dropping is biological or neurological in nature.

 

[Nickie]

v= 0I would first like to commend you for your interest in understanding the physics behind a bullet hitting the human body. It is an important topic, especially in today's world where gun violence is unfortunately prevalent.

Now, to address your question, you are correct in thinking that a bullet hitting the human body is a perfectly inelastic collision. This means that the two objects (bullet and person) stick together after the collision and move with a common final velocity. In this case, the bullet becomes embedded in the person's body.

To calculate the final velocity of the combined system (bullet and person), we can use the equation you mentioned: m1v1 + m2v2 = (m1+m2) v2f. In this equation, m1 and v1 represent the mass and initial velocity of the bullet, while m2 and v2 represent the mass and initial velocity of the person. The final velocity, v2f, is what we are trying to solve for.

However, in order to accurately calculate the final velocity, we also need to consider other factors such as the type of tissue the bullet hits, the angle at which it enters the body, and the speed and type of bullet. This is because the human body is not a uniform material and different tissues have different densities and resistances.

In addition to using the equation for perfectly inelastic collisions, we can also use the principles of momentum and force to understand the physics behind a bullet hitting the human body. Momentum is defined as the product of mass and velocity, and in a closed system (like a bullet and a person), the total momentum before and after a collision remains constant. This means that the momentum of the bullet before it hits the person is equal to the momentum of the combined system after the collision.

Furthermore, we also need to consider the force exerted by the bullet on the person's body. This force is determined by the mass, velocity, and density of the bullet, as well as the area of impact and the resistance of the body tissues. It is this force that causes damage to the body, and the extent of this damage depends on various factors.

In conclusion, the physics behind a bullet hitting the human body is a complex and multifaceted topic. It involves principles of momentum, force, and perfectly inelastic collisions to understand the final velocity and damage caused by the bullet. I hope this helps in your understanding of this subject.