SylvanCyborg

Do you believe a rocket that weighs several thousand kg can reach a speed of 17, 500 mph? For reference, this is over 80 football field lengths in one second. If so, can you please explain the details of how this is achieved?

When I see the rocket lift off and gain speed, it doesn't seem to zip away that fast. It may be going fast, but it's not going anywhere near 80 football fields per second. So when exactly is this speed achieved? At what burn stage? Does anyone have footage indicating this dramatic increase in speed? Is this about the speed it's going when we see the car in orbit?

It's picking up speed to get out of the earth into space, it doesn't reach that speed while it's accelerating though the atmosphere, it reaches that when it's in space. There's plenty of research out there that you could look up this answer yourself.

SylvanCyborg

It's picking up speed to get out of the earth into space, it doesn't reach that speed while it's accelerating though the atmosphere, it reaches that when it's in space. There's plenty of research out there that you could look up this answer yourself.

So when it's in the atmosphere, it's much slower? When it gets to space, that's when it starts speeding up? In the total vacuum of space, that's where it really throttles up?

JohnAdams1145

From the frame of reference of a person on the ground, it does indeed get that high. You don't notice it because they get far away pretty quickly. People notice things are fast because of their high angular speed, not actual speed. Imagine an airplane traveling 20 times faster but also 20 times farther away. Doesn't look so fast.

The rockets go full throttle in the atmosphere and certainly reach very high speeds; however, the main acceleration takes place in space to boost the orbit. The reason why rockets are launched straight up is to get out of the dense atmosphere quickly; then the rocket turns and accelerates "horizontally" (tangentially)

SylvanCyborg

From the frame of reference of a person on the ground, it does indeed get that high. You don't notice it because they get far away pretty quickly. People notice things are fast because of their high angular speed, not actual speed. Imagine an airplane traveling 20 times faster but also 20 times farther away. Doesn't look so fast.

The rockets go full throttle in the atmosphere and certainly reach very high speeds; however, the main acceleration takes place in space to boost the orbit. The reason why rockets are launched straight up is to get out of the dense atmosphere quickly; then the rocket turns and accelerates "horizontally" (tangentially)

Do you know how fast it's going while in the atmosphere? When it gets into space, is it able to get enough thrust to reach 17, 500 mph? Do you know what top speed is Falcon Heavy expected to reach while in space? Do you know approx what speed the car was going during the live stream?

From the frame of reference of a person on the ground, it does indeed get that high. You don't notice it because they get far away pretty quickly. People notice things are fast because of their high angular speed, not actual speed. Imagine an airplane traveling 20 times faster but also 20 times farther away. Doesn't look so fast.

The rockets go full throttle in the atmosphere and certainly reach very high speeds; however, the main acceleration takes place in space to boost the orbit. The reason why rockets are launched straight up is to get out of the dense atmosphere quickly; then the rocket turns and accelerates "horizontally" (tangentially)

Do you know how fast it's going while in the atmosphere? When it gets into space, is it able to get enough thrust to reach 17, 500 mph? Do you know what top speed is Falcon Heavy expected to reach while in space? Do you know approx what speed the car was going during the live stream?
Why are you asking here and not in a physics forum?

SylvanCyborg

Why are you asking here and not in a physics forum?

I'm asking here because one of the subjects of this forum is conspiracy. I believe we are being lied to about this launch. I believe that the claim that a rocket can travel 86 football field lengths within 1 second is ridiculous. The reason I'm asking for more stats is just out of genuine curiosity. I want to know what people who believe these lies really think is going on. Maybe I will ask in a physics forum. May I ask why you offered such a low content post? Nevermind, I don't care to know the answer to that.

Why are you asking here and not in a physics forum?

I'm asking here because one of the subjects of this forum is conspiracy. I believe we are being lied to about this launch. I believe that the claim that a rocket can travel 86 football field lengths within 1 second is ridiculous. The reason I'm asking for more stats is just out of genuine curiosity. I want to know what people who believe these lies really think is going on. Maybe I will ask in a physics forum. May I ask why you offered such a low content post? Nevermind, I don't care to know the answer to that.
Hence find out about the science of rockets that will tell you how they work somewhere without the rudeness that is common here.

SylvanCyborg

Hence find out about the science of rockets that will tell you how they work somewhere without the rudeness that is common here.

Just to clarify, can I then assume you are in agreement with the claim that the rocket travels 86 football field lengths within one second?

Hence find out about the science of rockets that will tell you how they work somewhere without the rudeness that is common here.

Just to clarify, can I then assume you are in agreement with the claim that the rocket travels 86 football field lengths within one second?
Why a claim and not fact?

SylvanCyborg

Why a claim and not fact?

Because I don't accept it as a fact. Clearly you do. As I said, I believe this claim is a lie. Thank you for sharing, and please feel free to off any additional claims you wish, or we can just leave it as agree to disagree.

Why a claim and not fact?

Because I don't accept it as a fact. Clearly you do. As I said, I believe this claim is a lie. Thank you for sharing, and please feel free to off any additional claims you wish, or we can just leave it as agree to disagree.
Where have you looked for further information?

SylvanCyborg

Where have you looked for further information?

One thing I looked at was how fast the fastest jet plane can reach. It seems to be the SR71 at a approx 3540 km/h (2199.654 mph). According to what I read, at this speed the thermal expansion starts to pull the plane apart. That's extremely fast. For reference, a bullet averages at 1,700 mph.

So when I'm told that the Falcon Heavy can travel 17, 500 mph, or about 86 football field lengths in one second, I'm very skeptical about that claim. I'm not sure what information could make me believe this claim, but I'm certainly willing to look at any additional information.

Speaking of which, are you planning to offer any information anytime soon? If not, let's agree to disagree and leave it at that.

Rama Set

Why a claim and not fact?

Because I don't accept it as a fact.

That isn’t how the world works unfortunately. There are lots of places to go research rocket technology and it appears you should. You should probably also adopt an agnostic position until you have a really solid ground not to. So far it appears that you don’t accept this claim solely on the basis that it sounds outlandish and that is a terrible basis.

SylvanCyborg


That isn’t how the world works unfortunately. There are lots of places to go research rocket technology and it appears you should. You should probably also adopt an agnostic position until you have a really solid ground not to. So far it appears that you don’t accept this claim solely on the basis that it sounds outlandish and that is a terrible basis.

Another one who agrees that the rocket travels 86 football field lengths in one second. Thank's for your input. Agree to disagree.

Rama Set


That isn’t how the world works unfortunately. There are lots of places to go research rocket technology and it appears you should. You should probably also adopt an agnostic position until you have a really solid ground not to. So far it appears that you don’t accept this claim solely on the basis that it sounds outlandish and that is a terrible basis.

Another one who agrees that the rocket travels 86 football field lengths in one second. Thank's for your input. Agree to disagree.

I said nothing of the sort, obviously. I said that you appear to be ignorant on the topic and operating from incredulity and that is no way to discern the truth.

SylvanCyborg


I said nothing of the sort, obviously. I said that you appear to be ignorant on the topic and operating from incredulity and that is no way to discern the truth.

So just to clarify, do you or do you not agree with the claim that the rocket travels 86 football field length in a single second? As I clearly stated, I do not agree with this claim. Do you have some problem with me asking this question? If so, maybe you should post some other place. I'm posting here about what I believe to be a conspiracy, that's the topic of my post. Are you ok with that? Did I upset you somehow?

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Offline nickrulercreator

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It starts slow, and speeds up. The acceleration is determined by a few things:

Engine power, mass, and drag. The engine power will become more powerful as the rocket nears space. This is because of the Tsiolkovsky Rocket Equation: https://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation. As the rocket burns its fuel, its mass decreases, making it easier to accelerate as well. Lastly, as the rocket nears space, the drag caused by air resistance and pressure put on the rocket decrease.

So, the higher the rocket goes, and the longer it burns, the faster it will travel, and the faster it will accelerate.

Because I don't accept it as a fact.

Like Rama Set said, that's not how the world works. It doesn't matter if you accept it or not, facts are facts. You can choose to believe them or not, but that doesn't discredit them.

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I believe this claim is a lie

Why?
This end should point toward the ground if you want to go to space. If it starts pointing toward space you are having a bad problem and you will not go to space today.

Rama Set


I said nothing of the sort, obviously. I said that you appear to be ignorant on the topic and operating from incredulity and that is no way to discern the truth.

So just to clarify, do you or do you not agree with the claim that the rocket travels 86 football field length in a single second?

For the record, I do. But it is largely irrelevant to your problem.

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As I clearly stated, I do not agree with this claim. Do you have some problem with me asking this question?
As I clearly stated, my problem with this is that you arrived at your decision from a place of ignorance and incredulity. You can’t even say what is wrong with something going that fast.

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If so, maybe you should post some other place.

Im fine here, but thanks for your concern.

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I'm posting here about what I believe to be a conspiracy, that's the topic of my post. Are you ok with that?
Of course I am.

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Did I upset you somehow?

Why should your ignorance be upsetting to me?


SylvanCyborg

With so many people calling me ignorant, I suppose I will have to admit defeat. It still seems impossible to reach these speeds in atmosphere, and I will stand by that assertion. However, once it gets to space, I really have no claim to make about what is possible.

In fact, I will go so far as to say, I don't know anything at all about space. As far as I'm concerned, this is a realm where literally anything can happen. I will never go there, I will never see it. I will only receive what NASA, SpaceX and other authorities tell me about it.

If I can please ask some people who have commented to indulge me with a final request on this topic?

I would just like to summarize some of the facts that people have put forth on this topic, and make sure I clearly understand. I know this may not be the best place to ask these questions, but I would greatly appreciate your input as a way to reach some level of closure for myself.

1. I've learned that air slows the rocket a lot. It can only reach 3,000 mph in atmosphere, but 18,000 mph at the edge of space. That increase is due to the lack of air resistance.

2. The atmosphere has essentially no effect on the amount of thrust. Whether in atmosphere, or in a total vacuum, the same level of thrust can be achieved.

Am I getting this correct? Any more information or corrections is greatly appreciated. Again, thank you for input, and allowing me to express my opinions on this matter.