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kallog #35189 06/29/10 03:59 PM
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Originally Posted By: Kallog
They did that on Mythbusters too.


I watched a mythbusters episode titled
" Air Cylinder Rocket " Season 4, Episode 21
that was debunking the possibilities
of using a compressed air cylinder to propel a small boat.

the method used was a simple pipe leading from the air cylinder to the rear of the boat , the pipe then turned 90 degrees downward , then turned 90 degrees horizontal again.

the exit where the air came out was apx 2 inches above the bottom of the boat.

the test started and as most boats do the boat took off , but this boat took off pretty fast , then it lost momentum.

they debunked it , I debunked them.

they didnt account for the boat riding on top of the water
so when the boat took off , the boat lifted up.

lifting the pipe out of the water...

compressed air cant push against air as good as it can against water so the boat lost momentum.

I wouldnt place much faith in the engineers on mythbusters.

heres a link to the section about the tank going through a brick wall.

through a wall

and heres a video showing part of the boat experiment.

overview of the episode

heres the effects of not venting a tank really impressive.

train tank car implodes-free vacume energy

shoot some steam in it , but dont vent it , and you get all
the free energy you could possibly need.

imagine a large piston...










3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
.
kallog #35190 06/29/10 04:33 PM
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I think that, for the overwhelming majority, the question of authenticity doesn't arise, since they are sufficiently in touch with reality. There may be some who, being perhaps unsophisticated or unaware of events, require updating before being convinced. Dealing with the conspiracy theorist is a different matter. To deign to point to the particular - e.g. the reflectors - as evidence, is a waste of time. Worse, it plays to the tune of the pathologically deluded. They have in place a mental barrier between their 'theory' and the deluge of data that we refer to as the real world. The typical response to any threat to that barrier is agitation and aggression.


"Time is what prevents everything from happening at once" - John Wheeler
paul #35191 06/29/10 04:58 PM
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When you blow up a balloon and release it, the balloon can fly all over the place for a short while. This doesn't happen because the air from the balloon is pushing against the air outside the balloon. It happens because the balloon pressure is no longer in equilibrium.

Imagine the balloon is tied off with the air inside. In that case, the pressure is equalized in all directions. It's pushing with constant pressure at every point inside the balloon. When you release the opening, the air inside the balloon is pushing against every place on the inside of the balloon - except the opening. The pressure is no longer in equilibrium.

This is a demonstration of Newton's third law. (Every action has an equal and opposite reaction.) The air coming out the balloon on the other side causes a force that is counter-balanced by the force on the other side that is pushing the balloon.

The same principle is what would make the compressed air canister work (or not work). I did not see the mythbuster's episode, but I'll look for it in future.

The same principle is what makes rockets work. It's not that the burning fuel is pushing against the air outside the rocket (although that happens, it's not what's producing the lift). Rather, the force of the expanding gas is pushing against the rocket and NOT pushing against the exhaust area.

And regarding the mirror panel left behind on the moon - it's irrelevant for the moon-hoaxers. I recently heard someone say that you can't reason a person out of an opinion they didn't use reason to get into in the first place. For those of us whose brains are not broken, it has produced highly relevant and useful information.

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Originally Posted By: TheFallibleFiend

The same principle is what makes rockets work. It's not that the burning fuel is pushing against the air outside the rocket (although that happens, it's not what's producing the lift). Rather, the force of the expanding


That's true, but I think having the exhaust underwater would slow the release of the air, applying less force to the boat, but lasting longer. Whether that'd make the boat travel a longer or shorter distance isn't clear to me. It would probably depend on lots of other factors.

Still, there's other ways to realize that compressed air isn't much use for vehicle propulsion. Like determining its energy content.

Still again, moving a boat at low speed (and ignoring waves) takes very little force, unlike a car which always has some friction regardless of speed. I wonder if you could actually travel a lot further in a boat on the same amount of energy as a car - as long as you go slow enough. ??


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Ah , but lift a BOAT PROPELLER up out of the water and see how fast the boat will go , by forcing the air backwards.

its basicaly a fan in water.

the boat did move as rapidly or more as a standard motorised boat would , momentarily.

and then as soon as the water moved under the boat , the boat lifted , and the rear of the boats bottom could be seen as in the below image.

and the pipe could be seen above water.

causing its momentum to decreased.



the mythbusters dishonestly busted this as the compressed air from the pipe is supposed to react against the water.

notice in the above image the boat propeller is still under the water , you cant even see it.

how many BOATS have you seen with propellers placed above the BOTTOM of the boat?

if the above moving boat were the boat that mythbusters used
the pipe that released the compressed air would be located at a height apx 2 inches above the water level seen at the rear of the boat in the above image.

But its a energy thing , they probably got a few bucks for this one.








3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
paul #35194 06/29/10 05:25 PM
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Originally Posted By: paul
Ah , but lift a BOAT PROPELLER up out of the water and see how fast the boat will go , by forcing the air backwards.

its basicaly a fan in water.


A boat propeller isn't optimized for air. Replace it with an aircraft propeller and engine of the same power and it would go faster. That's why swamp boats have bigger propellers than normal boats.

paul #35195 06/29/10 05:35 PM
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Yes. A propeller works on a slightly different principle. The shape of the propeller induces a pressure differential between the front and back of the prop. That differential induces the thrust.

Of course the third law applies, but also Bernoulli's principle (the same thing that makes a plane fly). A prop blade is a kind of wing, except that the rotational force is converted to thrust instead of lift. (Well, I guess on a helicopter, it's also converted to lift, but probably not a boat prop.)

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Kallog,
Agree on all counts.

Paul,
Again, I didn't see the mythbuster's episode, but unless they were somehow using the compressed air to power a prop, I don't understand the relevance of your reply.

kallog #35197 06/29/10 05:43 PM
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Originally Posted By: Kallog
A boat propeller isn't optimized for air.


and a jet of air isnt optimized for water.

but put the air at a sensible depth below the water , and the boat would not have lost momentum until it ran out of air pressure.

or better yet put a air motor behind a propeller then turn the propeller with the compressed air.

anyway , the shows results were clearly bought and paid for.

these guys are not that stupid.

I would like to see them redo this one correctly.





3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
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Originally Posted By: Kallog
I don't understand the relevance of your reply.


the relevance was to give a visual representation of where the
mythbusters placed the pipe that released the compressed air.

ie.. above the water line.

where the air could not possibly react against the water
once the boat began to move.

and it moved rapidly...


as for the relevance to this topic , it is to show that nay sayers will use any available method to accomplish their goal.

those that believe we didnt go to the moon are simple nay sayers , they havent got a drop of water in their bucket because their bucket wont hold any water.



3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
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Originally Posted By: TheFallibleFiend
Paul,
Again, I didn't see the mythbuster's episode, but unless they were somehow using the compressed air to power a prop, I don't understand the relevance of your reply.


I can see what Paul's saying. I'd certainly expect some difference in efficiency between underwater and out-of-water. But it might even be the other way round and wouldn't be enough to make it practical for actually travelling to places. Maybe enough for some sort of joy-ride tho.

Another weak reason why it still wouldn't work is after the boat got so fast the pipe was out of the water, that should have slowed it down until the pipe was back underwater, then sped up again, so basically got to some equilibrium position. But it didn't, it just ran out of air after a brief moment out of the water.

paul #35200 06/29/10 11:10 PM
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Originally Posted By: paul
anyway , the shows results were clearly bought and paid for.


Yes, paid for by you, the viewer through advertising. Its like the news, they tell the people what they want to hear because it's those same people who ultimately pay them.

But there's many other ways to show that compressed air isn't a practical substitute for petrol, which I suppose is partly what they were getting at - as well as how cartoons use it.

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Quote:
Both redewenur and TheFallibleFiend are as nutty as fruit cakes.


SHHHHH !!!

personaly I believe that NASA landed two men on the moon , but not first.

the Russians claim that prize.

they just didnt make it back and were most likely alive as the craft landed on the moon.

whats the big deal anyway , its not like it would take much to get there , just a burn or two.


3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
paul #35203 06/30/10 04:45 AM
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Is that belief based on information, or a blind desire to assume that everything you don't understand is wrong?

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Originally Posted By: preearth

Do you think that these two are really so stupid?

No. It is more likely they are propagandists.


Didn't psychologists find that overt homophobics are often repressed homosexuals?

But anyway, about your colliding planets. Could you please explain how the gravitational potential energy didn't melt the crust? I havn't actually done any calculations on that but I'd be amazed to find it might not melt.

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You are violating the terms of service with your insults and name-calling. You have been warned.


If you don't care for reality, just wait a while; another will be along shortly. --A Rose

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The Russia missions to plant French reflectors had limited success. They only recently located the first reflector. But we've been getting signal from the American reflectors since they were planted - one by each of three Apollo missions.

This doesn't prove the reflectors were not planted remotely, but it would explain why ours worked - we had people planting them in person, instead of robotic rovers.

Moreover, there is no good reason to think the moon landing was hoaxed - none. All of the so-called evidence is just silly stuff that has been refuted many times over. Your estimate of my intelligence or how well I can be trusted is irrelevant to me, as are all the rest of your opinions. Those opinions are also irrelevant to nearly everyone else on the planet judging by the success of your website.

kallog #35211 06/30/10 08:03 PM
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The Russian Moon Landing

some say its faked , but of course some say the U.S. Moon landings were faked.

I just found this today , so I havent examined it really well.


3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
paul #35213 07/01/10 05:59 AM
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Originally Posted By: paul
some say its faked , but of course some say the U.S. Moon landings were faked.


And some say the h****aust was faked. But sadly we know that happened just as they say it did, because people get locked up for making claims like that. The government is always right, especially when they punish dissidents. That just proves how right they are!

I mention that just in case you want to know what a real conspiracy looks like. It also involves social engineering so the general public will help in the job of persecuting anyone promoting officially-incorrect ideas.

kallog #35217 07/01/10 12:46 PM
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Some people say Einstein was a fake and that he didn't really author his ideas; other people say that Uri Geller is a fake psychic. Are those two claims equivalent?

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