Speed and distance of a bullet?

Question

Stange one i know, but thats what a bottle of white does for you!!!!!!! Just been watching a film which had lots of shooting in it, tell me.....if you were to shoot a bullet into the air, at what height would gravity take over and the bullet fall back to earth....AND....at what force would the bullet hit the ground at....as much force as it was first fired, or less??? Now there's a question for you einstein wannabees!!!!!!!!

Answer 1

... and that's why I stick to whiskey, not wine.

Answer 2

to get height of the bullet is easy, all you need is the initial vertical velocity and the force of gravity. The equation is (v_v^2)/2g, where v_v is the vertical velocity and g is gravity, on Earth 9.8 m/s^2.

SO, for example if you fired a bullet straight up, and the bullet travels at, say 500 m/s, the equation will be (500 m/s)^2/2(9.8 m/s^2) so that comes out to 250000 m^2/s^2/19.6 m/s^2 which equals 12,755.10 meters.

You also can mulitply that by 4 and find the maximum range if i shot the bullet at a 45 degree angle...which is 51,020 meters.

NOW i will freely admit that these are the equations for trajectory with no drag or wind, ie in a vacuum. Once you factor in those things the ranges become more like the ones we are used to for guns on Earth, but i dont feel like working out those equations :)

Oh and if we keep the scenario the same, i.e. in a vacuum, the force that it comes down with would be exactly the same that it went up with, in my example 500 m/s. In the real world with drag and winds it wont come down with enough force to kill you.

Answer 3

The muzzle velocity of any bullet is determined by power of the charge behind it,which can vary enormously depending on the calibre of the gun.Therefore the height it attains before falling back can also vary considerably.As to the speed of it on it's return journey, it can only ever reach "terminal velocity",which can vary between 125 and 150 M.P.H. depending on factors such as air density, temperature and atmospheric pressure at the time,but considerably slower than it's upward journey.(A bullet fired from a high velocity rifle could reach in excess of 2,000 M.P.H.) Nevertheless, I often wonder when I see newsreel clips of fanatics in the middle east firing bursts of celebratory machine gun fire into the air, just how often innocent people are hit by falling bullets. I certainly wouldn't want to be hit on the head by one.Even at 125 M.P.H. a glancing blow from a falling projectile could cause serious injury.If it were to hit you right in the middle of the top of your head it would almost certainly kill you.
Just a friendly word of advice. If you're thinking of holidaying in Tehran or Baghdad, it might be wise to pack a bullet-proof umbrella !

Answer 4

For the most part this probably doesn't answer your question, but I think it's interesting. Hypothetically, if you were to aim a gun exactly parallel with the ground; perpendicular to the height (horozontal), and fired that gun exactly the same time as dropping the same bullet from the same height of that gun, gravity would bring the bullet fired by the gun to the ground exactly the same time as the falling bullet.
I also believe that a bullet may surpass the sound barrier... but don't take my word.
-and the previous answer I heard almost the exact thing elsewhere on the internet... hmmm

Answer 5

That will depend on the coefficient of friction (air resistance of the bullet, the muzzle velocity, and the angle that you fire it at (from horizontal). Given actual data it's not that hard to work out.

The bullet will lose energy during it's entire flight, as it rubs against the air (air resistance), and therefore would not hit the earth with as much speed as it was launched. (final potential energy
Still I've always wondered whether you find mysteriously shot dead bodies far away when you see all these gun toting nutters firing guns into the air at extremist's funerals and celebrations.

Answer 6

Everything depends on the velocity of the bullet being fired into the air but the speed at which it falls is constant, 32 ft per second.

Answer 7

well the bullet would reach about 2400 feet if fired from a standard handgun (e.g. glock) and it would reach around 200 mph before it came down to earth cause the bullet is relying on gravity and not the gun it will accelerate slower and it wont get as much speed as if it were dropped from 20,000 feet it wont kill you but could injure you if you got hit by one by the way the handguns ammo usually doesnt go past mach 1 as the shape isnt effeciant enough to keep the bullet stable at those speeds

Answer 8

The height will be determined by the calibre, mass and charge. The bullet fall rate will be determined by the gravitational pull on the mass falling. I don't know how high it will go but when falling it will reach it's terminal velocity well before it hits the ground. but it will still be dangerous.

Answer 9

if the bullet falls the same distance as it traveled going up, then yes it will have the same force. tell me the initial velocity and mass of the bullet and i can tell you how high, that was the topic of our earlier physics classes.

Answer 10

It would have less energy than when fired.

The friction between the air & the bullet will absorb some of the initial energy.

Answer 11

Depending on the calibre of the bullet, and what powder it has inside to to propel the projectile.