Vagueness and the Aftermath - A sporadic diary

[tikay]

OK. I'd had a few and was a bit pissed off.

No more posts about gates until after the weekend I promise.

We'll take offence if there are.

[Rod Paradise]

And I still don't know why rockets don't tip over.

Damn you Red, I've been on an hour long google trail & my head hurts.

Simple answer (that explains nothing) is that the centre of thrust is kept behind the centre of gravity which keep the rocket upright.

Clumsy analogy is rear wheel drive car in icy conditions, if I'm driving it it'll spin out quickly, if my mate who is a beemer fan is driving it he'll take the car up roads and hills I'd hesitate to try in a 4x4. He's skilled, his corrective steering is precise, and he manages to balance the thrust of the car well enough not to spin out. - The modern rocket uses directional gimballed thrusters to make lots of very small corrections which we don't see.

If it goes wrong, the tip moves out of line and....

[Tal]

Simplistically, isn't it just that it's pointing in the right direction and the power it exerts exceeds the force of gravity acting on it?

Same reason the rocket escapes the Earth's gravitational pull when leaving its orbit.

[RED-DOG]

Simplistically, isn't it just that it's pointing in the right direction and the power it exerts exceeds the force of gravity acting on it?

Same reason the rocket escapes the Earth's gravitational pull when leaving its orbit.

No Sir Mr Tal.

The thrust of the rocket doesn't negate the other forces acting upon it.

Example:

Place a high powered rifle ten feet above and exactly parallel to the ground, fire it and and simultaneously drop a bullet from the same hight.

Both the fired bullet and the dropped one will hit the ground at the same time, proving that the enormous thrust propelling the fired bullet did not effect the effect of gravity.

If you fire a flightless arrow from a bow, it will turn end over end because any slight deviation from absolutely true will be instantly and exponentially magnified.

[tikay]

Place a high powered rifle ten feet above and exactly parallel to the ground, fire it and and simultaneously drop a bullet from the same hight.

Both the fired bullet and the dropped one will hit the ground at the same time, proving that the enormous thrust propelling the fired bullet did not affect the effect of gravity.


Really?

I'm struggling to get my head round that.

I know what you are saying, but it just feels so wrong.

That's the problem with science shite.

[doubleup]

.

[tikay]

^^^^

I've seen some bollocks spouted on blonde this week. Happy to say Tom's Bullet thing is not part of it.

I'm convinced.

Always said science was great.

[Rod Paradise]

Mythbusters also did a fantastic episode showing that if you shot something backwards out of a car moving forward at the same speed, the projectile falls straight down as if dropped from rest.

Re the rocket, I thought the question was why a long slender object moving at slow speed doesn't start to tumble, but I might have misunderstood.

[RED-DOG]

Mythbusters also did a fantastic episode showing that if you shot something backwards out of a car moving forward at the same speed, the projectile falls straight down as if dropped from rest.

Re the rocket, I thought the question was why a long slender object moving at slow speed doesn't start to tumble, but I might have misunderstood.

Yes Rod. It was exactly that.

[Tal]

Mythbusters also did a fantastic episode showing that if you shot something backwards out of a car moving forward at the same speed, the projectile falls straight down as if dropped from rest.

Re the rocket, I thought the question was why a long slender object moving at slow speed doesn't start to tumble, but I might have misunderstood.

Yes Rod. It was exactly that.

Ah. Then I misunderstood.

I don't know the answer to that question.

[RED-DOG]

Mythbusters also did a fantastic episode showing that if you shot something backwards out of a car moving forward at the same speed, the projectile falls straight down as if dropped from rest.

Re the rocket, I thought the question was why a long slender object moving at slow speed doesn't start to tumble, but I might have misunderstood.

Yes Rod. It was exactly that.

Ah. Then I misunderstood.

I don't know the answer to that question.

No problem Mr Tal. I didn't explain it very well. (Witness the fiasco with the gate question)
Rod's summing up was much clearer.

[RED-DOG]

We've had some rain here. Yesterday this brook was 4ft wide and 6in deep.

Click to see full-size image.

[bobAlike]

Mythbusters also did a fantastic episode showing that if you shot something backwards out of a car moving forward at the same speed, the projectile falls straight down as if dropped from rest.

Re the rocket, I thought the question was why a long slender object moving at slow speed doesn't start to tumble, but I might have misunderstood.

Yes Rod. It was exactly that.

Ah. Then I misunderstood.

I don't know the answer to that question.

No problem Mr Tal. I didn't explain it very well. (Witness the fiasco with the gate question)
Rod's summing up was much clearer.

No fiasco just a misunderstanding of what being asked.

[booder]

We've had some rain here. Yesterday this brook was 4ft wide and 6in deep.

Click to see full-size image.

How deep is it now?

[RED-DOG]

We've had some rain here. Yesterday this brook was 4ft wide and 6in deep.

Click to see full-size image.

How deep is it now?

8in?