Calculate KE of Projectile after Passing through Object.

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Calculating the kinetic energy lost by a projectile after passing through an object involves several variables, making it complex. Key factors include the bullet's shape and the material properties of the object it penetrates. A practical method to determine the energy loss is to measure the projectile's velocity after it exits the material. The kinetic energy can then be calculated using the formula Ek = 1/2 MxV^2. Accurate results typically require experimental data rather than theoretical calculations.
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Hi I am new to the forums and currently studying year 12 physics. I was wondering is it possible to calculate the Kinetic Energy lost from a projectile, say a bullet, after passing through an object, say a piece of steel. I know the weight of the bullet (41.9g) and it's initial KE (17,820J). I also know the density of the steel (7.85 g/cc) and its thickness (5mm).

Note please this isn't a homework question, it's just for my own curiosity and expansion of my own knowledge. Many thanks :)
 
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Welcome to PF!

HI PotatoSmasher! Welcome to PF! :smile:

No, there's too many variables …

it depends on the shape of the bullet, amongst other things …

if you were in CSI, you'd find the answer by actually firing bullets at a sample of the metal

that's really the only way :wink:
 
 
PotatoSmasher said:
Hi I am new to the forums and currently studying year 12 physics. I was wondering is it possible to calculate the Kinetic Energy lost from a projectile, say a bullet, after passing through an object, say a piece of steel. I know the weight of the bullet (41.9g) and it's initial KE (17,820J). I also know the density of the steel (7.85 g/cc) and its thickness (5mm).

Note please this isn't a homework question, it's just for my own curiosity and expansion of my own knowledge. Many thanks :)

All you need to do is measure the velocity of the projectile after it passes through the material and get its mass after you measure the velocity. Then it is Ek=1/2 MxV^2.
Paul
 
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