Reply to: HD Felix Baumgartners space jump

[SpontaneousOrder]

Yes indeed.
I guess the point is that if you fire a bullet horizontally from Baumgartners's capsule, that bullet will be going at, say, 1000mph. Which is much less than the 16,000 mph that it would require to stay in orbit. At 1000mph the effect of the curvature of the earth would be there, but small, resulting in the bullet hitting the ground a little later than the object dropped stationary, but not by very much (again assuming zero air resistance).

Muzzle velocity of the SA-80 is 940 meters per second if I remember right, so just over half a mile per second.
So from felix's height that makes about 50 miles + any extra for earth's curvature (i.e. hardly any difference as you say). About 30 feet.

**edit** that is - 30 feet extra drop, over a 50-ish mile horizontal flight.

[KentPhilip]

Which wouldn't make any sense when it was the mechanics of achieving orbit which sparked the discussion in the first place.

If 'sideways' motion had no effect the the astronauts would fall like stones fro the sky straight down to their deaths.

Yes indeed.
I guess the point is that if you fire a bullet horizontally from Baumgartners's capsule, that bullet will be going at, say, 1000mph. Which is much less than the 16,000 mph that it would require to stay in orbit. At 1000mph the effect of the curvature of the earth would be there, but small, resulting in the bullet hitting the ground a little later than the object dropped stationary, but not by very much (again assuming zero air resistance).

[SpontaneousOrder]

Here you go,

Ok, fine. My troll sense is weak today.

[EternalOptimist]

Here you go,

no one is arguing with this.

but what happens if you throw one sideways, or up ?

[SpontaneousOrder]

If you also ignore the curvature of the earth then yes.

Which wouldn't make any sense when it was the mechanics of achieving orbit which sparked the discussion in the first place.

If 'sideways' motion had no effect the the astronauts would fall like stones fro the sky straight down to their deaths.

[scooterscot]

Which Hits The Ground First?

Here you go,

[KentPhilip]

You can't talk about shooting bullets horizontally and dropping stones while assuming that they will 'occupy the same gravitational field'. BUT... if we assume that differences in gravitational field strength are negligible up to very high altitudes, then you're still wrong.

Drop a stone from felix's balloon, and shoot another at high speed horizontally. Suppose no atmosphere (a vacuum) for simplicity. Are you telling me both will hit the ground at the same time?

If you also ignore the curvature of the earth then yes.

[SpontaneousOrder]

Oh dear -



No it will not. Both objects shall hit the ground at the same time for as long as they occupy the same gravitational field.

You can't talk about shooting bullets horizontally and dropping stones while assuming that they will 'occupy the same gravitational field'. BUT... if we assume that differences in gravitational field strength are negligible up to very high altitudes, then you're still wrong.

Drop a stone from felix's balloon, and shoot another at high speed horizontally. Suppose no atmosphere (a vacuum) for simplicity. Are you telling me both will hit the ground at the same time?

[EternalOptimist]

Oh dear -



No it will not. Both objects shall hit the ground at the same time for as long as they occupy the same gravitational field.

if two objects fall, yes. but the bullet is ballistic.

what happens if you fire it upwards ?

[scooterscot]

Oh dear -

I.e lets say that the stone fall time is 1 second. After 1 second the bullet will still be in flight. .

No it will not. Both objects shall hit the ground at the same time for as long as they occupy the same gravitational field.

[EternalOptimist]

when I started typing this, I was a million miles away from where you are now.

so next time you accuse me of being off topic... fck the fck off

[SpontaneousOrder]

Why do you think the bullet has further to fall?

Given a static third party frame of reference, then the stone will move down amount Y, and sideways amount X (which is zero). The bullet will move the same Y amount down, plus amount X sideways (which we're not too bothered about, other than the fact that having moved sideways X, the bullet will not be on the ground yet.

I.e lets say that the stone fall time is 1 second. After 1 second the bullet will still be in flight. This is obviously precisely how orbits are achieved - the sideways speed is sufficient that an orbiting bullet would never hit the ground.

[EternalOptimist]

Well no they wouldn't, that's the point Given a perfect sphere for an earth, the bullet has further to travel 'down' due to the curvature of the earth.

space might be curved, but scooterscot is totally bent

[scooterscot]

Well no they wouldn't, that's the point Given a perfect sphere for an earth, the bullet has further to travel 'down' due to the curvature of the earth.

Why do you think the bullet has further to fall?

[SpontaneousOrder]

I hope I just din't read someone suggesting angular momentum was reason why the space station remains in orbit. I blame Mr Gove.

Here's one for the mentally challenged amongst you. Throw a stone from the same height at the same time the hammer strikes the bullet and both bullet and stone will fall to hit the ground at the same time.

Well no they wouldn't, that's the point Given a perfect sphere for an earth, the bullet has further to travel 'down' due to the curvature of the earth.