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Author Topic:   Flat Earth Society
Rrhain
Member
Posts: 6351
From: San Diego, CA, USA
Joined: 05-03-2003


Message 47 of 119 (819099)
09-06-2017 3:51 AM
Reply to: Message 38 by CRR
09-04-2017 8:06 PM


CRR writes:
quote:
I was surprised to find that Neil deGrasse Tyson believes in a flat Earth. Here's what he said;
quote:
A bullet fired level from a gun will hit ground at same time as a bullet dropped from the same height. Do the Physics.
Neil deGrasse Tyson (@neiltyson) August 11, 2010 50 Awesome Quotes by Neil deGrasse Tyson » TwistedSifter
Do the physics and you will find this is only true on a flat Earth.
Only for extremely fast bullets. Guns don't fire bullets that fast.
It's easy to test: Just get yourself a very long testing ground and rig up a gun and a bullet such that the bullet drops right when the gun goes off. Then, time how long it takes each bullet to hit the ground.
Wait...Mythbusters did that. What do you think they found?

Rrhain

Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

Minds are like parachutes. Just because you've lost yours doesn't mean you can use mine.

This message is a reply to:
 Message 38 by CRR, posted 09-04-2017 8:06 PM CRR has not replied

  
Rrhain
Member
Posts: 6351
From: San Diego, CA, USA
Joined: 05-03-2003


Message 48 of 119 (819100)
09-06-2017 4:11 AM
Reply to: Message 46 by CRR
09-05-2017 9:50 PM


Re: Neil deGrasse Tyson is a Flat Earther!
CRR writes:
quote:
I must admit I was surprised myself at the difference the Earth's curvature could make over a few kilometers. I wonder where we could find a flat (i.e. spherical) plain of sufficient extent to confirm this experimentally?
It's called a "lake." Any sufficiently large one will do. If the earth were flat, then the surface of the water on the lake would also be flat since water levels itself out.
So get yourself on the dock and set up a sufficiently powered light source (a common laser will do). Put yourself on a boat with a target and note where on the target the laser hits. Then, simply putt on out into the lake, paying attention to where the laser hits the target. If you pay attention to the distance you've traveled, the distance between the two laser targets, and the particular direction you traveled, you'll be able to calculate the precise curvature and thus calculate the size of the earth.
You will notice that as you get further away from the laser, it will rise up the target as the earth curves away.
There was some TV show on either PBS or Discovery that did this.
But even then, that's just a demonstration of just how "small" the earth is. You don't need any fancy equipment. It's how the Ancient Greeks figured out the earth was round: The shadows cast by the sun. At noon on a specific day, calculate the angle of a shadow cast from a plumb at two different locations. You will find that they are different. Again, if you pay attention to the difference in angle, the distance between your two measurements, and the direction in which those two locations are (assuming they aren't on the same parallel), you'll be able to calculate the curvature and thus the size of the earth.
Which is precisely what Eratosthenes did and got an astoundingly accurate estimate for the size of the earth (using a well at Syene and the Pole at Alexandria).
quote:
In a similar vein I also say Galileo was wrong in his experiment dropping weights off the leaning tower of Pisa; the heavy one should hit the ground first.
And you would be wrong. There is no evidence that he actually did so but rather set it up as a thought experiment.
But then again, they did this on the moon with a hammer and a feather.

Rrhain

Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

Minds are like parachutes. Just because you've lost yours doesn't mean you can use mine.

This message is a reply to:
 Message 46 by CRR, posted 09-05-2017 9:50 PM CRR has replied

Replies to this message:
 Message 49 by NoNukes, posted 09-06-2017 9:35 AM Rrhain has not replied
 Message 53 by CRR, posted 09-06-2017 5:57 PM Rrhain has replied

  
Rrhain
Member
Posts: 6351
From: San Diego, CA, USA
Joined: 05-03-2003


Message 55 of 119 (819137)
09-06-2017 9:15 PM
Reply to: Message 53 by CRR
09-06-2017 5:57 PM


Re: Galileo was wrong
CRR responds to me:
quote:
The gravity is lower so they fall slow enough to be observed.
Irrelevant. That the lower gravity means you can easily see the two masses falling at the same rate without special equipment doesn't mean they aren't falling at the same rate or that a higher gravitation field would change anything about the relationship of their paths with respect to each other. Gravity is gravity.
quote:
There is close to a vacuum so air resistance doesn't affect the fall.
That's kinda the point. You do understand how air resistance would impart a separate force and thus would complicate a measurement of the gravitational field, yes? Not that it can't be done, mind you, but that it complicates a simple experiment. That's why there is such a thing as "terminal velocity" in a fluid.
You do understand how terminal velocity works, yes?
quote:
Earth however has atmosphere. Two objects of different masses, same material, same shape, will fall at different rates due to air resistance.
Again, that's kinda the point. Do you not understand what Galileo was referring to?
And that he actually understood a bit about air resistance?
And thus he never actually carried out the experiment because of his understanding of air resistance but was referring to a thought experiment?
Do you even know what the actual thought experiment was?
Hint: String.
Here's another hint: There is an effect that corresponds to your claim regarding massive objects and their behaviour in gravitational fields. It's part of the reason why there is a retroreflector on the moon: It allows us to measure the distance between the earth and the moon and can be used to detect this effect (the name is for you to look up as homework.)
It has never been detected.
quote:
In the case of cannon balls this would only be detectable with very precise measuring equipment, such as would not have been available to Galileo, but it will make a slight difference and the heavier one will fall faster.
So no, you don't understand air resistance, how gravity works, or anything about Galileo's work.
Do you know how to calculate terminal velocity?

Rrhain

Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

Minds are like parachutes. Just because you've lost yours doesn't mean you can use mine.

This message is a reply to:
 Message 53 by CRR, posted 09-06-2017 5:57 PM CRR has not replied

  
Rrhain
Member
Posts: 6351
From: San Diego, CA, USA
Joined: 05-03-2003


Message 64 of 119 (819224)
09-08-2017 3:08 AM
Reply to: Message 61 by CRR
09-07-2017 6:08 PM


Re: Do the Math!
CRR writes:
quote:
So the heavy one will fall faster, although as I said the difference would have been undetectable for Galileo.
Incidentally, I remember seeing/hearing that Galileo was repeating an experiment performed by someone else. Good science to replicate the experiment.
Nope. Everything you have said regarding Galileo is wrong.
That isn't the experiment he was talking about. I asked you directly if you could describe it for us and so far, you have failed to do so.
Second, he never actually did the experiment. Again, that's because he wasn't talking about what you are claiming he was.
So let's try this again: What was the specific thought experiment that Galileo described?
Hint: String.

Rrhain

Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

Minds are like parachutes. Just because you've lost yours doesn't mean you can use mine.

This message is a reply to:
 Message 61 by CRR, posted 09-07-2017 6:08 PM CRR has replied

Replies to this message:
 Message 66 by CRR, posted 09-08-2017 3:28 AM Rrhain has replied

  
Rrhain
Member
Posts: 6351
From: San Diego, CA, USA
Joined: 05-03-2003


(1)
Message 65 of 119 (819226)
09-08-2017 3:20 AM
Reply to: Message 62 by Porkncheese
09-08-2017 1:02 AM


Re: Crepuscular rays
Porkncheese writes:
quote:
I don't buy the flat earth view but there is one argument that I cannot find a satisfying explination for. Crepuscular rays.
Why? Where do you think those rays reconverge? That is, if the light were strong enough and the atmospheric conditions were right such that you could see them go all the way across the sky, where do you think they would go? Just radially out forever?
No, they don't. If the conditions are right, you can see it and you get what are called "anticrepuscular rays."
And sure enough, they converge at the antisolar point. That's the spot directly opposite the sun. For example, if it's noon and the sun is directly overhead, then the antisolar point is directly below you.
So you have lines that appear to originate from the sun, wrap around the earth, and then reconverge directly opposite that point. That only happens if they are parallel...just like what you see regarding parallel lines receding into the distance like the typical example of train tracks.
If you could change your orientation regarding those shadows and rays, you would see them directly as being parallel:
http://blogs.discovermagazine.com/...-parallel/#.WbJESsh94vg
If you could be more specific as to why you are having difficulty projecting a three-dimensional effect into two dimensions, we will be better able to assist.

Rrhain

Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

Minds are like parachutes. Just because you've lost yours doesn't mean you can use mine.

This message is a reply to:
 Message 62 by Porkncheese, posted 09-08-2017 1:02 AM Porkncheese has replied

Replies to this message:
 Message 68 by Porkncheese, posted 09-08-2017 4:40 AM Rrhain has replied

  
Rrhain
Member
Posts: 6351
From: San Diego, CA, USA
Joined: 05-03-2003


Message 90 of 119 (819283)
09-08-2017 8:15 PM
Reply to: Message 66 by CRR
09-08-2017 3:28 AM


Re: Do the Math!
CRR responds to me:
quote:
OK, Happy now?
Nope.
Because, once again: He never actually did that.
Just like Newton was never hit on the head by an apple and suddenly came up with his theory of gravity.
It's a popular story and pleasant to consider, but he never actually did it.
Instead, he had another experiment in mind.
quote:
If it wasn't Galileo then it was Simon Stevin and Jan Cornets de Groot. And if Galileo did perform the experiment then he was replicating Stevin & de Groot.
Nope. They were in the Netherlands, not Pisa.
Since you seem to be incapable of doing your homework, let me educate you. He described it in his treatise, On Motion:
Consider two objects, one heavy and one light, connected by a string. If you were to drop them, what would happen?
Well, if objects fall at the same rate regardless of mass, then the combined object would fall as fast as each individual object.
But if there is a discrepancy, if lighter objects fall more slowly, then the lighter object would start to fall behind, creating a drag upon the larger object as the string became taut and the combined object would fall more slowly than the heavier object.
But the combined object is necessarily heavier than the individual heavy object so if heavier objects fall faster, the combined object should fall faster than heavier object on its own.
Thus, we have a contradiction: This object should fall both faster and slower than the heavier object alone. That cannot be. Therefore, the original assumption that heavier objects fall faster than lighter ones is shown to be false. Instead, they fall at the same rate.
You should consider reading what he actually wrote about the motion of falling bodies. Have you read Two New Sciences? In it, he discusses the motion of bodies falling down an inclined plane where he noted that they fell consistently. He then worked out that you could increase the angle of the plane to perpendicular and you'd describe a body in free-fall.
And it's there that he pointed out that you would need to have a vacuum in order to directly show that the effect on gravity on falling bodies is uniform, regardless of mass.
So clearly, Galileo understood that air resistance has an effect upon falling bodies and that you need to account for it.
You can easily work this out given the equations for force and gravitation:
F = ma => a = F/m
F = GMm/r^2 (M is mass of earth and m is mass of object)
a = (GMm/r^2) / m => GM/r^2
Notice that the mass of the object cancels out and the acceleration is based solely upon the mass of the earth and the distance between the objects.
Besides, the Pisa experiment has been carried out. And sure enough, the balls hit at the same time.
And if you still can't wrap your head around it, be aware that the experiment has been recreated at Pisa:

Rrhain

Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

Minds are like parachutes. Just because you've lost yours doesn't mean you can use mine.

This message is a reply to:
 Message 66 by CRR, posted 09-08-2017 3:28 AM CRR has replied

Replies to this message:
 Message 96 by CRR, posted 09-10-2017 6:08 AM Rrhain has replied

  
Rrhain
Member
Posts: 6351
From: San Diego, CA, USA
Joined: 05-03-2003


Message 91 of 119 (819284)
09-08-2017 8:23 PM
Reply to: Message 68 by Porkncheese
09-08-2017 4:40 AM


Re: Crepuscular rays
Porkncheese responds to me:
quote:
All your questions
Huh? You're the one with the questions. What are you talking about?
quote:
are answered in the link i provided including practical demonstrations.
Huh? I'm not here to engage in argument by footnote. You're the one with the objections. You need to present them for yourself.
Use your words.
My post has already answered all the objections raised in that video. So now what?
Time for you to use your words and answer the question put to you: Exactly what is your objection?
Be specific.
I have one expected question, so let me respond with a question of my own:
What's the difference between rays you see in the sky and the rays through a piece of cardboard at your feet? More specifically, where are you in relation to the ray on the left versus the ray on the right? How close are they to each other? How might the visible appearance of those rays be affected by your position with respect to them?
Are you still having trouble projecting a three-dimensional scenario into two dimensions?

Rrhain

Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

Minds are like parachutes. Just because you've lost yours doesn't mean you can use mine.

This message is a reply to:
 Message 68 by Porkncheese, posted 09-08-2017 4:40 AM Porkncheese has not replied

Replies to this message:
 Message 93 by jar, posted 09-08-2017 8:33 PM Rrhain has not replied

  
Rrhain
Member
Posts: 6351
From: San Diego, CA, USA
Joined: 05-03-2003


Message 92 of 119 (819285)
09-08-2017 8:32 PM
Reply to: Message 75 by Porkncheese
09-08-2017 9:36 AM


Re: Crepuscular rays
Porkncheese writes:
quote:
And even if we simply dissmiss their evidence as garbage or whatever I don't think perspective can account for such a wide spread of rays covering almost 180 degrees as shown here
Except that's precisely what perspective accounts for:
Question: Where are you in relation to the ray on the right compared to the ray on the left? How far away is it? From whence does it originate?
And more importantly, as I directly asked you: Where does it go? If you were to track it across the sky (that is, turn around), whither does it go?
Exactly how does a straight ray behave? Surely you aren't saying that the gravitational pull of the earth is significantly affecting these rays? Besides, if it were, shouldn't those rays be pulled in rather than splayed out?
So we're back to the question you have avoided:
Where do those rays go?
And you have some more to answer:
Where are you in relation to those rays? Where is the one on the left compared to the one on the right?

Rrhain

Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

Minds are like parachutes. Just because you've lost yours doesn't mean you can use mine.

This message is a reply to:
 Message 75 by Porkncheese, posted 09-08-2017 9:36 AM Porkncheese has not replied

  
Rrhain
Member
Posts: 6351
From: San Diego, CA, USA
Joined: 05-03-2003


Message 102 of 119 (819419)
09-10-2017 7:34 PM
Reply to: Message 96 by CRR
09-10-2017 6:08 AM


Re: Do the Math!
CRR responds to me:
quote:
Galileo would have been correct for objects falling in a vacuum.
And did he or did he not understand that? Have you read his works, particularly on falling bodies?
quote:
However in air you get air resistance which alters the results; and the faster they fall the greater the air resistance, until the object reaches terminal velocity.
Nice try. That's my argument to you. You *do* recall that I directly asked you about this, yes? Message 55, in case you forgot.
quote:
When the string becomes taut it will then apply additional acceleration to the smaller ball and retard the heavier one. The combined object will then fall at a speed somewhere between that of the two balls individually.
Really? You don't think the tension caused by the string might affect the orientation of the objects with respect to their motion through the air, thus altering their velocity?
What falls faster through the air: A skydiver whose axis from head to toe is perpendicular to the direction of motion or one whose axis is parallel?
See, this is why you keep stumbling. You're ignoring the very thing that Galileo understood.
And all because you don't actually understand the experiment Galileo was proposing.
quote:
However, as I have said, these effects would have not been observable for 16th century observers.
Strange...Galileo observed it directly. That's why he talked about it.
This is a direct question. If you deign to respond to this post, I specifically request that you answer this one question:
Have you read Galileo's work?
Your entire response history regarding this seems to be predicated upon a fallacious understanding of what Galileo wrote. So I really want to know:
Have you read Galileo's work?
quote:
So Galileo was wrong
No, he wasn't. It is clear you haven't read his work and thus don't understand what he actually said.
quote:
Newton was wrong
No, he wasn't. More accurately, his original point that force is the derivation of momentum with respect to time is correct. The error was in assuming a linear rather than relative universe such that F = dp/dt then reduces to ma. Even in a relative universe, F = dp/dt is still correct.
quote:
and Neil deGrasse Tyson was wrong.
No, he wasn't.
You clearly don't understand what he said or was referring to.

Rrhain

Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

Minds are like parachutes. Just because you've lost yours doesn't mean you can use mine.

This message is a reply to:
 Message 96 by CRR, posted 09-10-2017 6:08 AM CRR has replied

Replies to this message:
 Message 103 by CRR, posted 09-10-2017 10:00 PM Rrhain has replied

  
Rrhain
Member
Posts: 6351
From: San Diego, CA, USA
Joined: 05-03-2003


Message 106 of 119 (819498)
09-11-2017 7:20 PM
Reply to: Message 103 by CRR
09-10-2017 10:00 PM


Re: Do the Math!
CRR responds to me:
quote:
quote:
If you deign to respond to this post, I specifically request that you answer this one question:
Nah, it's not worth it.
So that means no, you haven't.
Well, no wonder you don't understand a thing about what Galileo said and keep getting the physics wrong.

Rrhain

Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

Minds are like parachutes. Just because you've lost yours doesn't mean you can use mine.

This message is a reply to:
 Message 103 by CRR, posted 09-10-2017 10:00 PM CRR has not replied

Replies to this message:
 Message 108 by NoNukes, posted 09-13-2017 4:04 PM Rrhain has not replied

  
Rrhain
Member
Posts: 6351
From: San Diego, CA, USA
Joined: 05-03-2003


Message 112 of 119 (820220)
09-17-2017 3:59 PM
Reply to: Message 110 by Porkncheese
09-14-2017 1:10 AM


Re: Dude, seriously
Pokrncheese writes:
quote:
Dude... I never said the earth wasn't round.
No, you said the sun is close and perspective isn't real.
You still haven't answered the direct questions I asked of you:
Where are you in relation to the ray on the left compared to the ray on the right? How far away are they?
And most importantly: Where do they converge? If you followed them across the sky...you know, turned around...where do they go?

Rrhain

Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

Minds are like parachutes. Just because you've lost yours doesn't mean you can use mine.

This message is a reply to:
 Message 110 by Porkncheese, posted 09-14-2017 1:10 AM Porkncheese has not replied

  
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