Author Topic: Episode #61  (Read 14016 times)

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Offline azinyk

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Episode #61
« Reply #15 on: September 26, 2006, 01:02:29 PM »
Quote from: "Joe Shmoe"
The cubic time manifesto is classic paranoid/schizophrenic.  I like the phrase "word salad" because it is a perfect example of the kind of writings that you will find from someone so deeply out of sync with reality.


I know Steve is a neurologist, but having skimmed the Time Cube page, I wouldn't call what I saw "word salad".  Loose association, maybe.  He does have problems with language, not seeming to distinguish between adverbs, adjectives, and nouns, for instance (e.g. "You are a stupid" instead of "You are stupid", "think opposite" instead of "think oppositely").  These are still symptoms of schizophrenia, but they're not word salad, as far as I can see.

Offline azinyk

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Episode #61
« Reply #16 on: September 26, 2006, 03:31:52 PM »
Regarding the question of the canal locks:

The larger boat displaces more water, so when the water level is high, there is less water in the lock, and more boat.  However, when the water level is lower, the lock is not empty.  The boat is still floating, so its displacement is the same.

Suppose the lock holds 10 million litres without a ship in it, and 3 million litres when the water is low.  The displacement of the kayak is about 100 L (it is about 100 kg with the passenger inside) and the displacement of the ship is about 1 million L (it weighs 1000 tons).  The contents of the lock will be:

            Water high     Water low     Difference
Liner       9000000 L      2000000 L     7000000 L
Kayak       9999900 L      2999900 L     7000000 L

For either boat, the amount of water used to cycle the lock is the same.

Fortunately, the question is a lot more interesting than that.  Suppose the liner wants to go down, the water level in the lock is initially high, and the lock is fed by a reservoir at the top.  When the liner moves from the reservoir into the lock, the reservoir loses 1 million L of ship and gains 1 million L of water (which flowed out of the lock when the ship entered).  After the liner decends, there will be more water in the reservoir than there would have been if the kayak had decended.  Now let's suppose that another liner wants to come up.  The water level is still low after the first liner exited the lock.  The ship enters, pushing out 1 million L of water.  The gates close, and 7 million L enters the lock to cycle it.  The ship exits, but there is less water in the top reservoir since the lower water source contributed less water, because the ship was taking up space.

As long as the same displacement tonnage of boats goes up as goes down, it works out that there's no net gain or loss.  If you have a lot of ships going down and a lot of kayaks coming up, you keep more water in the top reservoir (in the short term).

A couple more issues: small boats share the lock, so instead of using a lockful of water for one kayak, you divide that water by all the boats sharing the lock.  On the other hand, if you're carrying cargo, one big ship can carry more cargo than a lockful of little boats, so the amount of water used per unit of cargo is less for the big ship.

Ashley Zinyk

Offline Joe Shmoe

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Episode #61
« Reply #17 on: September 26, 2006, 08:10:40 PM »
Quote
YOU DESERVE DEATH -
FOR SINGULARITY EVIL
in the  Universe of Antipodes,
opposite hemispheres & sexes.
No God  Can Make Himself.


The first sentence.  Word salad as I understand it means that the words flow in a disjointed fashion, like the stream of thought.  Someone whose brain isn't functioning creates sentence fragments and joins meaningless phrases.  I'll agree that this isn't the worst case of word salad ever, but it is a clearly reminiscent.  Also I would argue that this may be slightly edited to be more cogent or entirely fabricated.

As an aside: I don't believe that someone suffering from formal thought disorder would be capable of making a functioning website

Offline Steven Novella

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Episode #61
« Reply #18 on: September 26, 2006, 08:48:23 PM »
Regarding word salad - some parts of the website were more structured than others. At its worst it degenerated past the point that I would say it is incoherent - disjointed idea fragments. Not the most extreme word salad I have personally experienced, but worthy of the designation. But this is a minor point of semantics.

Someone who has even a severe thought disorder is not necessarily technically dysfunctional. Of course, the extreme end is catatonia - the inability to function at all. But there is a degree of severity where someone has very paranoid "flight of ideas" and disordered thought, but could still operate basic technology. The website itself has no real structure or complexity. He could have published it quite easily.
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Offline azinyk

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Episode #61
« Reply #19 on: September 27, 2006, 12:53:13 PM »
I sent this to the panel by e-mail, then thought that other listeners might like to read it:

I think Randi made a mistake in Episode #61 (around 4min 05sec), with regard to lightning rods.  He said that they don't conduct lightning "unless they're poorly grounded".  I tentatively accepted that, and planned to look up further information later.  The more I thought about it, though, the less it made sense. My previous idea of how lightning rods worked was that the current flowed harmlessly through a metal conductor instead of through something that might catch fire or explode.  But how could a lightning rod work without conducting the lightning?  Previous stories of lightning hitting the Sears Tower, the space shuttle, etc. agreed better with the conventional explanation.

I looked this up in the first reference I had handy, the 1977 "How it Works" encyclopedia.  Volume 10 supported my notion of how lightning rods work, and had a photograph of lightning striking a rod, which Randi said shouldn't exist.  However, another volume of that encyclopedia says "Scientists don't know how dowsing works, but we know that it does", so clearly the reference wasn't rock-solid.

However, when I got access to the web, I found a 2004 article in "Electricity Today", and a 2002 article from the American Meteorological Society that support the traditional theory.  It seems that there are controversial "lightning eliminators" that their proponents claim can prevent strikes entirely, although electrical engineers and physicists seem to be lined up against them.  In any case, we can be sure that conventional lightning rods work by getting hit, instead of letting the lightning hit something else.

Maybe Randi was giving us a deliberate test of our credulousness, or our respect for authority.  In a recent podcast, Steve took us to task for only listening to podcasts by people who already share our ideas.  In which case, I hope I passed the test.


Ashley Zinyk

references:
http://www.lightningsafetyalliance.com/documents/lightning_war.pdf
http://www.lightningsafety.com/nlsi_lhm/Uman_Rakov.pdf

Offline Freeman74

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Episode #61
« Reply #20 on: September 27, 2006, 02:11:24 PM »
According to this site Randi is right (Mostly). It seems that a lighting rod is to discharge the cloud gradually to prevent a strike. However if conditions do not allow for this a strike could occur then the rod would direct the energy of the strike to the ground instead of the structure. It does not say that a properly grounded lightning rod will never be struck though.

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Offline JHGRedekop

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Episode #61
« Reply #21 on: September 27, 2006, 02:25:38 PM »
Quote from: "Freeman74"
According to this site Randi is right (Mostly). It seems that a lighting rod is to discharge the cloud gradually to prevent a strike. However if conditions do not allow for this a strike could occur then the rod would direct the energy of the strike to the ground instead of the structure. It does not say that a properly grounded lightning rod will never be struck though.


I think there's a combination of things going on. For the most part, a lightning rod is supposed to bleed off charge to prevent the build up of a high voltage difference between the structure and the clouds (thereby preventing a strike). But really tall structures (such as the CN Tower, which I can see from my window) present a very tempting target for lightning. They may be more designed to take the lightning strikes so that neighbouring structures aren't threatened. Certainly, the CN Tower gets hit an awful lot...

Offline swpalmer

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Episode #61
« Reply #22 on: September 27, 2006, 02:50:06 PM »
The bit about the lightning bothered me as well.

I would think that a properly grounded lightning rod would get struck because it would present the path of least resistance for the charge in the cloud to discharge to earth.

I can see how it would slowly bleed off charge in the atmosphere before the charges involved built to the point that it would spark (lightning) though.  But doesn't the lightning normally go between the earth and a storm cloud?  

Lightning rods on buildings like barns are no where near as high as the clouds that the lightning would come from in that case, so how would they be involved in preventing the build up of the charge?

And then there is the idea that if the charge can bleed off slowly through a lightning rod, why can't it bleed off slowly directly to the building or ground?  I was under the impression that the building is likely to be similar to ground in its electrical potential, it just doesn't conduct very well.  If it wasn't similar in potential to the ground the building wouldn't be a target for something trying to discharge to ground in the first place.


On another note, has anyone viewed the videos from MIT of Time Cube guy, Gene Ray? I can't understand a word the guy is saying.  I must be stupid and evil.

Offline kmorgan

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Episode #61
« Reply #23 on: September 27, 2006, 03:50:08 PM »

Offline swpalmer

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Episode #61
« Reply #24 on: September 27, 2006, 04:15:01 PM »
Assuming the HowStuffWorks site got it right, it confirms that lightning rods ARE designed to be hit by lightning.  By being a path of least resistance they channel the electrical energy to ground better than the structure they are protecting and thus take the bulk of the energy so the structure doesn't explode and catch fire.

It seem Randi was referring to this:
Quote
If the structure that you are attempting to protect is out in an open, flat area, you often create a lightning protection system that uses a very tall lightning rod. This rod should be taller than the structure. If the area finds itself in a strong electric field, the tall rod can begin sending up positive streamers in an attempt to dissipate the electric field.

as if that was the only thing a lightning rod is designed to do.

Offline ramboelmo

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Episode #61
« Reply #25 on: September 28, 2006, 11:43:18 PM »
Lighting rods are most definately suppose to help equalize the charge in the air.  I am sure their are cases where lightning hits the rods but that is not the main purpose of them.  This is what Ben Franklin was study how to help prevent them. I hope the lightning rods on my house are not suppose to get hit by lightning since they are pure metal with no protective covering on them.

Offline Carl

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Episode #61
« Reply #26 on: September 29, 2006, 08:10:45 AM »
Whether lightning rods help to disperse the build up of charge (thereby preventing a significant potential difference from building) or simply help to conduct a lightning strike via a safe path to the ground is largely dependent upon the prevailing atmospheric conditions.

The charge that builds up within a thunderstorm resides upon the surface of the cloud droplets and precipitation that form within the cumulonimbus. Therefore the lightning rod can only dissipate the charge from those cloud droplets and precipitation that it comes into contact with.

Books and articles on storm clouds tend to represent a straightforward picture where the ground is positively charged and the cloud negatively charged, or vice versa. However, this is not always the case. Often lightning strikes pass from one part of a cloud to another part of the same cloud, producing what we call sheet lightning. Sometimes they pass between separate, neighbouring cumulonimbus cells too.

What this means is that your hypothetical building with a lightning conductor could be negatively charged and be sat within a cloud layer that also has a negative charge. In this scenario the conductor will not be disspating any charge because it has the same polarity as the surrounding cloud. A lightning strike could then occur from an area of positively charged cloud at the top of the cumulonimbus down to the region in which the conductor sits. The metal conductor will then provide the path of least resistance for the strike to pass through that region.

In short then, a conductor works in both of the ways described.

Offline Steven Novella

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Episode #61
« Reply #27 on: September 29, 2006, 02:08:24 PM »
I talk about this on this week's episode (uploaded shortly). Randi is basically correct, and these experiments were done by Ben Franklin himself. But if lightening does strike, the rod will divert it harmlessly into the ground (hopefully).
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Offline Manny G.

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Episode #61
« Reply #28 on: September 30, 2006, 12:03:43 PM »
Exactly as bradburyc describes.  I'm a noob here... and just caught up on the podcasts.

Thought I'd add my 2c.

The problem with lightning rods as with most things in Physics is that they are not as simple as they sometimes appear.

Simply put:

Lightning rods have several functions:

1. (As Randi said) They do "leak" off charge from ground to help reduce electric potential in the area.  (This can actually be done by any object... not even a strongly conductive one (though conductive materials are more efficient at it)... trees do this... a steeple on a church, etc... this explains the shape of the lightning rod... it directs the charge upward and a strike downward but that's next)

2.  They act as grounds for lightning strikes to safely carry the extreme current away from the structure in question if 1) doesn't eliminate the charge in the area... often it won't if there is not a large difference between the height of the rod and the surrounding area.

3.  Similarly, to do both they are likely higher than the surrounding structures and do have an increasing likelihood to be hit as their relative height increases... the Sears Tower... Empire State building... or more recently as captured on NASA video, the Shuttle launch platform has a large extended lightning rod to protect the sensitive equipment inside as well as the shuttle which was attached at the time. (You may recall they had a day's delay to check on this as well.)
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Offline Adair

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Episode #61
« Reply #29 on: October 02, 2006, 09:19:08 AM »
I was the one who wrote in about the 9/11 comment, and yes it was the first I heard of it!
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