Bullets and Gravity

[Arese]

Hold on a minute.

So you're saying that if a bullet is fired from a gun 1m above ground, and a bullet is dropped by hand from the same height at the same time, that they will both hit the ground at the same time?

bks.

[tribbles]

Yes, it will.

[Mattt]

s3fella said:

Does rifling on a gun barrel produce any sort of "lift" on a bullet, or does the spinning action do quite the opposite, it destroy any aerodynamic lift?

I used to think it did, because when I zeroed my rifle, it was dead on at 12 yards, then 35 yards. Between those distances you aimed below the target.

Then I realised it was just because the scope is mounted higher than the barrel and the line of sight passes through the trajectory twice

[ewenm]

Arese said:

Hold on a minute.

So you're saying that if a bullet is fired from a gun 1m above ground, and a bullet is dropped by hand from the same height at the same time, that they will both hit the ground at the same time?

bks.

If fired horizontally, yes. If you can produce some physics to prove otherwise, please do so.

[Justayellowbadge]

Bullet & Gravity.

It's this season's Plane & Conveyor, dahlings.

[Matt_N]

Arese said:

Hold on a minute.

So you're saying that if a bullet is fired from a gun 1m above ground, and a bullet is dropped by hand from the same height at the same time, that they will both hit the ground at the same time?

bks.

You havent read any of the links in the thread have you?

The laws of physics are not bks as you so eloquently put it.

[Arese]

ewenm said:

Arese said:

Hold on a minute.

So you're saying that if a bullet is fired from a gun 1m above ground, and a bullet is dropped by hand from the same height at the same time, that they will both hit the ground at the same time?

bks.

If fired horizontally, yes. If you can produce some physics to prove otherwise, please do so.

I can't produce the physics just at this present time, because frankly I'm too thick.

But, surely a bullet dropped from 1m would take no more than 0.5s to hit the floor.

If I fired a bullet from a gun at 1m height, and it hit the ground less than 0.5s later, that would be pretty crap.

I'm flummoxed.

[Johnnytheboy]

Arese said:

Hold on a minute.

So you're saying that if a bullet is fired from a gun 1m above ground, and a bullet is dropped by hand from the same height at the same time, that they will both hit the ground at the same time?

bks.

Would you expect it to take more or less time?

[FasterFreddy]

Arese said:

ewenm said:

Arese said:

Hold on a minute.

So you're saying that if a bullet is fired from a gun 1m above ground, and a bullet is dropped by hand from the same height at the same time, that they will both hit the ground at the same time?

bks.

If fired horizontally, yes. If you can produce some physics to prove otherwise, please do so.

I can't produce the physics just at this present time, because frankly I'm too thick.

But, surely a bullet dropped from 1m would take no more than 0.5s to hit the floor.

If I fired a bullet from a gun at 1m height, and it hit the ground less than 0.5s later, that would be pretty crap.

I'm flummoxed.

Er.... you're not supposed to point the gun down at the ground...

[s3fella]

Arese said:

ewenm said:

Arese said:

Hold on a minute.

So you're saying that if a bullet is fired from a gun 1m above ground, and a bullet is dropped by hand from the same height at the same time, that they will both hit the ground at the same time?

bks.

If fired horizontally, yes. If you can produce some physics to prove otherwise, please do so.

I can't produce the physics just at this present time, because frankly I'm too thick.

But, surely a bullet dropped from 1m would take no more than 0.5s to hit the floor.

If I fired a bullet from a gun at 1m height, and it hit the ground less than 0.5s later, that would be pretty crap.

Not if it had travelled half a mile in the process of dropping a metre it couldn't be (crap I mean!)

[ewenm]

Arese said:

ewenm said:

Arese said:

Hold on a minute.

So you're saying that if a bullet is fired from a gun 1m above ground, and a bullet is dropped by hand from the same height at the same time, that they will both hit the ground at the same time?

bks.

If fired horizontally, yes. If you can produce some physics to prove otherwise, please do so.

I can't produce the physics just at this present time, because frankly I'm too thick.

But, surely a bullet dropped from 1m would take no more than 0.5s to hit the floor.

If I fired a bullet from a gun at 1m height, and it hit the ground less than 0.5s later, that would be pretty crap.

I'm flummoxed.

Bullets are really fast (some are really really fast!) when fired from a gun so travel a long way in the time it takes to fall the 1m in height. It may seem counter intuitive but there is only one force pulling the bullet to the ground - gravity - and it's the same force whether the bullet has been dropped or fired.

[Matt_N]

Arese said:

ewenm said:

Arese said:

Hold on a minute.

So you're saying that if a bullet is fired from a gun 1m above ground, and a bullet is dropped by hand from the same height at the same time, that they will both hit the ground at the same time?

bks.

If fired horizontally, yes. If you can produce some physics to prove otherwise, please do so.

I can't produce the physics just at this present time, because frankly I'm too thick.

But, surely a bullet dropped from 1m would take no more than 0.5s to hit the floor.

If I fired a bullet from a gun at 1m height, and it hit the ground less than 0.5s later, that would be pretty crap.

Why would it be crap?

The force of gravity acting on each bullet is the same.

[dirty doug]

I think PH may have to introduce an I.Q. test as a condition of joining.

I don't want to exclude anybody though, so perhaps the results could be colour coded in the name so we are aware of what kind of brain we are talking to.

Just an idea....

edit for spelling... notch my colour back a bit.....

Edited by dirty doug on Tuesday 1st June 14:19

[Bibbs]

Arese said:

If I fired a bullet from a gun at 1m height, and it hit the ground less than 0.5s later, that would be pretty crap.

I'm flummoxed.

The sights make you aim above that. You are actually shooting slightly up in the air.

At almost 900metes per second, shooting a target 100m away, the bullet will not drop much at all.

[EvoDelta]

I'm glad this thread arrived. I tried explaining this to a friend the other day, but he would not believe me. I'll be sending him this link.

[Pesty]

EvoDelta said:

I'm glad this thread arrived. I tried explaining this to a friend the other day, but he would not believe me. I'll be sending him this link.

Ive tried this before. nobody ever belives me.

Its probably the only thing I remeber from my O level Physics,

Horizontal movement has no effect on the force of gravity. I even tried to re create it with ping pong balls

Muzzel velocity is what gives different weapons their range when fired horizontaly

[Arese]

dirty doug said:

I think PH may have to introduce an I.Q. test as a condition of joining.

I don't want to exclude anybody though, so perhaps the results could be colour coded in the name so we are aware of what kind of brain we are talking to.

I don't know of any IQ tests that have a physics element. Thankfully, or I clearly wouldn't have an IQ of 152.

I just can't get my head around the fact that the downwards gravitational pull isn't affected by other forces, in this case the force from the gun.

So, if a bullet left a 1m high gun at 1000mph (for the sake of argument), it would still hit the ground at the same time as me dropping one by hand from the same height. Wow.

I'm going to pass this around the office and show all the thickies how clever I am

[SystemParanoia]

http://www.youtube.com/watch?v=5C5_dOEyAfk

feather hammer drop

[ewenm]

I think there are still certain assumptions about local Euclidean geometry (i.e. we assume the world is flat for the purposes of the experiment). If you're dealing with very high speeds, the fact the world isn't flat but is the surface of an approximate sphere comes into play.

[OnTheOverrun]

Perhaps any in-house physics experts could extrapolate the following to convince the non-believers:

The longest range recorded for a sniper kill currently stands at 2,475 m (2,707 yd) and was achieved by CoH Craig Harrison, a sniper from the Household Cavalry of the British Army which was achieved using an L115A3 and a .338 Lapua Magnum round. The rounds travel at an average speed of 251m/s over that distance (ie fastest when they leave the barrel and slowing due to drag) meaning they took 6.017 seconds flight time at 251.8 m/s (826 ft/s) velocity and have dropped 120.95 m (4,762 in) or in angular units 48.9 milliradian (168 MOA) on their way.

Now let us consider that the round was fired from a prone position meaning the chamber was approximately 6 inches above the ground and that had the round not hit the target, it's flight time would've been longer than 6.017 seconds, do you still think an identical round dropped at the same time would take more than 6 seconds to fall six inches?



ETA - the clue is in the above text. . . . .

Edited by OnTheOverrun on Tuesday 1st June 14:55