Why Is a Bullet More Damaging Than Falling Out of Bed?

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The discussion centers on the comparison of the damaging effects of a bullet versus falling from a bed. The kinetic energy of a bullet fired from a Walther PPK is calculated to be approximately 622.05 J, while the gravitational potential energy of a person resting 1 meter above the ground is similarly around 622.3 J. The key point made is that a bullet causes more damage due to its smaller surface area, which concentrates impact force on a small area, whereas the impact from a fall is distributed across the body. The calculations for both energies are confirmed to be accurate, emphasizing the significant difference in damage potential. Overall, the conversation highlights the physics behind the lethality of bullets compared to minor falls.
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1. Bond's usual gun of choice in every movie is a Walther PPK (except when he can get his hands on a machine gun
which blows up more guys). A bullet like this has a mass of around 15g and leaves the gun at 288m/s. Calculate the
kinetic energy in a bullet like this.
2.Aside from shooting bad guys, Bond has a lot off success with, ummm, the ladies. Imagine he is resting in bed one morning
1 m off the ground and that his mass is 63.5 kg. What is his potential energy relative to the ground when he in bed?
3. Do answers from (1) and (2) surprise you? Why is a bullet more damaging than falling out of bed from a height of 1 m?

2. I think i have to use the formula of kinetic energy. Kinetic energy = (mv^2)2 and gravitational potential energy = mgh
sorry i can't use the codes properly so i wrote it this way :redface:

3. For number 1 i did

E_k=(mv^2)/2
= (0.015)(288^2)/2
=622.05 J
=6.22 x 10^2 J
so the kinetic energy is 6.22 x 10^2 J
Is this approximation correct since the question has 3 sig figs?

for number 2 i did

Eg=mgh
=63.5 x 9.80 x 1
=622.3 J
=6.22 x 10^2 J
so the gravitational potential enegry is 6.22 x 10^2 J
Is it also appropriate?

for number 3 i wrote
A bullet is more damaging than falling out of bed from height of 1 m because a bullet with its smaller surface area causes more impact on the small area thus creating more damage where is the pressure by falling one meter is spread through the whole body enabling the body to dissipate the damage and get less hurt.

Is it accurate?
 
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looks fine, except that you wrote different speeds, 288 and 228 :)
 
thank you.sorry that was a typing error. so is my third answer correct i mean is it alright to use those terms i used? also can i ask some more questions related to this topic in here? :)
thank you very much
 
Kinetic energy is 1/2 mv^2
 
mgb_phys said:
Kinetic energy is 1/2 mv^2
yes i did write that :)
i just wrote the whole thing and divided by two :)
 
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