Understanding through Discussion


Welcome! You are not logged in. [ Login ]
EvC Forum active members: 63 (9072 total)
550 online now:
Aussie, AZPaul3, kjsimons, PaulK, Phat, Tangle, Tanypteryx (7 members, 543 visitors)
Newest Member: FossilDiscovery
Post Volume: Total: 893,201 Year: 4,313/6,534 Month: 527/900 Week: 51/182 Day: 23/16 Hour: 1/4


Thread  Details

Email This Thread
Newer Topic | Older Topic
  
Author Topic:   A test of your common sense
RAZD
Member (Idle past 641 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 106 of 137 (666054)
06-21-2012 2:18 PM
Reply to: Message 102 by Taz
06-21-2012 12:02 PM


Hi Taz,

Usually, the beam will fail in the region adjacent to one of the loads. However, if the beam is elastic enough, it may fail in the middle region. ...

The engineer/s use these diagrams to assess all the potential failure locations and modes, and then designs the beam to withstand each of the stresses.

At the ends you have vertical sheer loads and bearing loads. The foundations (triangle and roller) have bearing loads.

At the load positions you have vertical sheer (from loading) and horizontal sheer (from bending), bending and bearing loads.

What the diagram tells the engineer is that the stresses in between these points are less than those at these points, so they only need to asses the stresses at these 4 locations to design the beam ... usually with a factor of safety.

Where the beam actually fails is due more to the characteristics of the beam -- is it flexible like rubber or fragile like glass -- and on what is deemed to be failure (how much deflection is allowed, ultimate versus yield strengths) than on the loads.

Enjoy.


we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


• • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •

This message is a reply to:
 Message 102 by Taz, posted 06-21-2012 12:02 PM Taz has taken no action

  
fearandloathing
Member (Idle past 3381 days)
Posts: 990
From: Burlington, NC, USA
Joined: 02-24-2011


Message 107 of 137 (666059)
06-21-2012 4:56 PM
Reply to: Message 100 by 1.61803
06-21-2012 10:50 AM


Intuitively I would of said the middle. But knowing this is a trick question I then thought point (A) since the surface area is less at the apex.

My first thought was the middle also because as a general rule of thumb when drilling a 2x8,10,12...ect you stay out of the middle 3rd. The size of the hole is determined in a similar way, 2x10= a 3 1/2 inch hole, 2x12....4 1/2 inch hole. There is a lot more to it, but I won't bore you.


“A nation of sheep will beget a government of wolves.”
― Edward R. Murrow

"You don't have to burn books to destroy a culture. Just get people to stop reading them" - Ray Bradbury


This message is a reply to:
 Message 100 by 1.61803, posted 06-21-2012 10:50 AM 1.61803 has taken no action

  
Tangle
Member
Posts: 8491
From: UK
Joined: 10-07-2011
Member Rating: 2.5


(1)
Message 108 of 137 (666062)
06-21-2012 5:22 PM
Reply to: Message 102 by Taz
06-21-2012 12:02 PM


Taz writes:


Usually, the beam will fail in the region adjacent to one of the loads. However, if the beam is elastic enough, it may fail in the middle region. In this particular case, the end condition is set to fail. Left end more than right end.

You see, when some of us gave you the "well it depends" answer which gave the circumstances when it would fail in each of those places, we were accused of 'over thinking the problem'. Now the answer turns out to depend on those exact same assumptions.

I really do think you picked the wrong audience.


Life, don't talk to me about life - Marvin the Paranoid Android

This message is a reply to:
 Message 102 by Taz, posted 06-21-2012 12:02 PM Taz has replied

Replies to this message:
 Message 110 by Taz, posted 06-21-2012 5:42 PM Tangle has taken no action

  
Taz
Member (Idle past 2527 days)
Posts: 5069
From: Zerus
Joined: 07-18-2006


(2)
Message 109 of 137 (666066)
06-21-2012 5:35 PM
Reply to: Message 105 by ringo
06-21-2012 1:57 PM


Common sense is hit or miss. There are cases where common sense will suffice. But the problem is it could miss just as well as hit.

My example does relate to the EvC debate. Why do you think there are so many engineers who are creationists? Just because you're an expert in one field doesn't mean you can speak with authority in another. As is demonstrated by this thread.

There are some very intelligent people here from all kinds of backgrounds. And my one little example frustrated people enough to have dropped my member rating from 8.0 to 6.9... and it's probably still dropping. Think how frustrating it must be for the creationist engineers. To them, life is obviously "designed".

I specifically brought in a simple engineering problem for a reason. Look at how many people insisted that the diagram did not have enough info. As an experiment, I went ahead and showed this diagram to 4 other engineers. The moment they saw the diagram, they all gave their answer right away. No need to know what the beam is made of or all the other nonrelevant details that members here insisted they needed. Heck, I went ahead and showed this to an architech and he gave his answer right away without enquiring for more details.

What the members here did by insisting the diagram made no sense or didn't have enough info was overstepping their boundaries and trying to tell the 2 engineers here what's what. Sound familiar? Here in EvC, we get creationists trying to tell scientists what's what all the time.

I'm also appalled at how many people switched to defensive mode when they realized they were confused by the diagram.

Again, I wasn't even looking for a specific engineering answer. A simple guess would have done it. I'm not here to laugh at anyone. Just disappointed I saw the same reaction/behavior I usually see in creationists when confronted with confusion.


This message is a reply to:
 Message 105 by ringo, posted 06-21-2012 1:57 PM ringo has replied

Replies to this message:
 Message 111 by Rahvin, posted 06-21-2012 6:03 PM Taz has taken no action
 Message 113 by Dr Adequate, posted 06-21-2012 8:59 PM Taz has replied
 Message 129 by ringo, posted 06-22-2012 12:08 PM Taz has taken no action

  
Taz
Member (Idle past 2527 days)
Posts: 5069
From: Zerus
Joined: 07-18-2006


Message 110 of 137 (666067)
06-21-2012 5:42 PM
Reply to: Message 108 by Tangle
06-21-2012 5:22 PM


Tangle writes:

You see, when some of us gave you the "well it depends" answer which gave the circumstances when it would fail in each of those places, we were accused of 'over thinking the problem'. Now the answer turns out to depend on those exact same assumptions.


Well, I would have accepted the "well, it depends...". But some people here were asking for really non-relevant details with a lot of technical verbose.

As I said in my previous post, I showed this to 4 engineers and 1 architect and they all gave an answer right away.

And as I explained, the answer isn't that important. It's how people reacted. Notice how many went into defensive posture. Some even calling the diagram nonsense.

I really do think you picked the wrong audience.

No, I think I picked the right audience. No one is an expert in everything. I don't know jack shit about geology, for example (pardon my french). That doesn't make me any less of an engineer. Not knowing the answer to this problem doesn't make you any less of whatever the hell you are. And yet here we are having a bunch of very intelligent people going into defensive mode over a simple diagram.

Edited by Taz, : No reason given.

Edited by Taz, : No reason given.


This message is a reply to:
 Message 108 by Tangle, posted 06-21-2012 5:22 PM Tangle has taken no action

Replies to this message:
 Message 112 by Coyote, posted 06-21-2012 6:44 PM Taz has replied

  
Rahvin
Member (Idle past 198 days)
Posts: 3966
Joined: 07-01-2005


(1)
Message 111 of 137 (666069)
06-21-2012 6:03 PM
Reply to: Message 109 by Taz
06-21-2012 5:35 PM


Again, I wasn't even looking for a specific engineering answer. A simple guess would have done it. I'm not here to laugh at anyone. Just disappointed I saw the same reaction/behavior I usually see in creationists when confronted with confusion.

The overestimation of self-competence is a human trait, not simply a Creationist one. It's a big part of why tests are used in schools and other professional training programs - without an objective test to measure one's own competence in a subject, people will tend to think themselves much more competent than they actually are.

And for some reason we culturally prefer to give an answer, even when based upon ignorance, other than a truthful and shameless "I don't know." The best "common sense" answer provided in the thread was "I don't really know, I'd ask an engineer."


“The human understanding when it has once adopted an opinion (either as being the received opinion or as being agreeable to itself) draws all things else to support and agree with it.”
- Francis Bacon

"There are two novels that can change a bookish fourteen-year old's life: The Lord of the Rings and Atlas Shrugged. One is a childish fantasy that often engenders a lifelong obsession with its unbelievable heroes, leading to an emotionally stunted, socially crippled adulthood, unable to deal with the real world. The other, of course, involves orcs." - John Rogers

“A world that can be explained even with bad reasons is a familiar world. But, on the other hand, in a universe suddenly divested of illusions and lights, man feels an alien, a stranger. His exile is without remedy since he is deprived of the memory of a lost home or the hope of a promised land. This divorce between man and his life, the actor and his setting, is properly the feeling of absurdity.” – Albert Camus

"...the pious hope that by combining numerous little turds of
variously tainted data, one can obtain a valuable result; but in fact, the
outcome is merely a larger than average pile of shit." Barash, David 1995.


This message is a reply to:
 Message 109 by Taz, posted 06-21-2012 5:35 PM Taz has taken no action

  
Coyote
Member (Idle past 1342 days)
Posts: 6117
Joined: 01-12-2008


Message 112 of 137 (666073)
06-21-2012 6:44 PM
Reply to: Message 110 by Taz
06-21-2012 5:42 PM


I showed this to 4 engineers and 1 architect and they all gave an answer right away.

And that answer is...


This message is a reply to:
 Message 110 by Taz, posted 06-21-2012 5:42 PM Taz has replied

Replies to this message:
 Message 114 by Taz, posted 06-21-2012 9:05 PM Coyote has taken no action

  
Dr Adequate
Member (Idle past 287 days)
Posts: 16112
Joined: 07-20-2006


(1)
Message 113 of 137 (666083)
06-21-2012 8:59 PM
Reply to: Message 109 by Taz
06-21-2012 5:35 PM


Taz writes:

No need to know what the beam is made of or all the other nonrelevant details that members here insisted they needed.

Taz writes:

Usually, the beam will fail in the region adjacent to one of the loads. However, if the beam is elastic enough, it may fail in the middle region.

Edited by Dr Adequate, : No reason given.


This message is a reply to:
 Message 109 by Taz, posted 06-21-2012 5:35 PM Taz has replied

Replies to this message:
 Message 115 by Taz, posted 06-21-2012 9:07 PM Dr Adequate has replied

  
Taz
Member (Idle past 2527 days)
Posts: 5069
From: Zerus
Joined: 07-18-2006


Message 114 of 137 (666084)
06-21-2012 9:05 PM
Reply to: Message 112 by Coyote
06-21-2012 6:44 PM


Combo of what I said. Again, I wasn't looking for a definitive answer with 20 pages of mathematical proof and 20 days of intense experiments inside a $200 million facility. Just simply look at the diagram and tell me what you think.

With simply supported beams or anything that's long and hard and full of seamen... or just long and hard, failure tend to occur adjacent to where the point loads are. Most of the time, it's either one or the other, although it could occur at both places. In this particular case, the left end is set up to fail. Now, if failure occurs as a result of bending, then more than likely the middle region would fail.


This message is a reply to:
 Message 112 by Coyote, posted 06-21-2012 6:44 PM Coyote has taken no action

Replies to this message:
 Message 116 by fearandloathing, posted 06-21-2012 9:33 PM Taz has taken no action

  
Taz
Member (Idle past 2527 days)
Posts: 5069
From: Zerus
Joined: 07-18-2006


Message 115 of 137 (666085)
06-21-2012 9:07 PM
Reply to: Message 113 by Dr Adequate
06-21-2012 8:59 PM


Silly DrA, hasn't it occurred to you that that's part of the answer? You mean to tell me life is more complicated than a classic text book problem?

This message is a reply to:
 Message 113 by Dr Adequate, posted 06-21-2012 8:59 PM Dr Adequate has replied

Replies to this message:
 Message 117 by Dr Adequate, posted 06-21-2012 9:53 PM Taz has taken no action

  
fearandloathing
Member (Idle past 3381 days)
Posts: 990
From: Burlington, NC, USA
Joined: 02-24-2011


Message 116 of 137 (666091)
06-21-2012 9:33 PM
Reply to: Message 114 by Taz
06-21-2012 9:05 PM


In this particular case, the left end is set up to fail

If left is A then I am right.... (for all the wrong reasons no doubt)......Off to play the lottery now


“A nation of sheep will beget a government of wolves.”
― Edward R. Murrow

"You don't have to burn books to destroy a culture. Just get people to stop reading them" - Ray Bradbury


This message is a reply to:
 Message 114 by Taz, posted 06-21-2012 9:05 PM Taz has taken no action

  
Dr Adequate
Member (Idle past 287 days)
Posts: 16112
Joined: 07-20-2006


Message 117 of 137 (666093)
06-21-2012 9:53 PM
Reply to: Message 115 by Taz
06-21-2012 9:07 PM


Silly DrA, hasn't it occurred to you that that's part of the answer? You mean to tell me life is more complicated than a classic text book problem?

What?

P.S:

Taz writes:

No need to know what the beam is made of or all the other nonrelevant details that members here insisted they needed.

Taz writes:

Usually, the beam will fail in the region adjacent to one of the loads. However, if the beam is elastic enough, it may fail in the middle region.

Taz writes:

Your reply is the most common misconception that I was referring to. Most people would say the middle, which is of course wrong.

Edited by Dr Adequate, : No reason given.


This message is a reply to:
 Message 115 by Taz, posted 06-21-2012 9:07 PM Taz has taken no action

  
Minnemooseus
Member
Posts: 3879
From: Duluth, Minnesota, U.S. (West end of Lake Superior)
Joined: 11-11-2001
Member Rating: 2.7


Message 118 of 137 (666094)
06-21-2012 10:06 PM
Reply to: Message 102 by Taz
06-21-2012 12:02 PM


Why you ignore the moose?
Usually, the beam will fail in the region adjacent to one of the loads. However, if the beam is elastic enough, it may fail in the middle region. In this particular case, the end condition is set to fail. Left end more than right end.

Minnemooseus, in message 5, writes:

Assuming the beam was rigidly fixed at A and able to move on roller at D, I think the greatest stress would be at A - The beam would fail at A (the support/beam connection at A would fail).

You never replied to my message 5.

Moose


This message is a reply to:
 Message 102 by Taz, posted 06-21-2012 12:02 PM Taz has taken no action

  
Bolder-dash
Member (Idle past 2866 days)
Posts: 983
From: China
Joined: 11-14-2009


Message 119 of 137 (666099)
06-21-2012 10:32 PM


I think this thread has become one of the most enlightening topics about the evolution-creation debate.

First we have an engineer asking people to use common sense to solve a poorly diagrammed question. Later we found but that the question isn't even solvable given the data we have been given, but then we are told the answer doesn't matter.

Now Taz is suggesting that an engineer who is a creationist has no business commenting about evolution, because it is not their field of study, and thus they can't have an informed opinion about it,

And so does this mean that a physicist can't have an informed opinion about evolution? How about a medical doctor? Or an anatomist? Or an archeologist. For that matter, virtually NONE of the science fields are a study of evolution. My good friend has a Ph.D in molecular biology. He told me his expertise has zero to do with the Theory of Evolution, and that it is entirely meaningless to his work. He doesn't know how leopards gained spots, or a walking stick evolved to look like a twig.-any lay person on the street is as informed about this question as he is.

And that's just it, nobody knows about evolution. Who is an expert on the entire field of evolutionary study, you show that person to me? Is Richard Dawkins, the guy who doesn't even know the full name of Charles Darwins book? Is P.Z. Meyers the expert we should defer to? He can't even debate the subject, so he hides behind a highly censored blog, which is more like a Don Rickles insult act. Is Eugenie Scott the expert? She states that one shouldn't even attempt debating the subject, because they will be made to look like fools.

How about Lawrence Krauss, the theoretical physicist who imagines floating waves of strings or other dimensions we can never see, writing on Huffingtonpost about evolution? Is he the expert we should bow to and say-oh well, they must know something we don't? Or is the expert Neil Shubin, he actually has a Ph.D. in organismic and evolutionary biology, and he has no idea what mechanisms formed a cell. He says that the same recipe for development forms all of our organs from teeth to breast, but he has absolutely no idea where this recipe came from and why. And he still is arguing that Tiktallic is a transition from fish to land animals even though its existence was millions of years after tetra-pods were already walking on the earth. Is he the expert that knows everything we don't, so we should just close our eyes and believe him?

This is what virtually every form of media, and every website on the internet that deals with evolution wants us to accept-that somewhere (who knows where) there is some expert scientist who knows all about evolution, but his name is a secret. But believe us, they know. And so when e tell you evolution is a fact, its because we have faith that an expert has told us it is so. Who are we to doubt. if they tell us that the reason a diver can perform a perfect 3 1/2 inward pike somersault with perfect balance and timing, while at the same time their brain is monitoring 100's of different functions of their eyes and heart and breathing, is because a few billion years ago some kind of chemical (again please don't ask what) was very sloppy at multiplying and kept breaking down and screwing up.

You see if there was a plan, none of this could have happened, life as we see it can only exist if there was so much chaos that everything was in constant flux and constantly unpredictably mutating and malfunctioning. Its the whole malfunctioning of random mixes of chemicals, that's why we have a brain that can do somersaults, and math, and read poetry. Its just a bunch of bad accidents with paint. An expert knows this to be true. What Taz wants you to know is that you should just believe him (please stop asking who!!, its a gay, ****** guy with an IBM ok?), because common sense can't figure this out.

Thank you for that Taz. Only the experts can understand evolution, it defies common sense! So true Taz, so true.


Replies to this message:
 Message 120 by Dr Adequate, posted 06-21-2012 11:03 PM Bolder-dash has taken no action
 Message 122 by Tangle, posted 06-22-2012 3:53 AM Bolder-dash has replied
 Message 123 by frako, posted 06-22-2012 4:21 AM Bolder-dash has taken no action

  
Dr Adequate
Member (Idle past 287 days)
Posts: 16112
Joined: 07-20-2006


(1)
Message 120 of 137 (666103)
06-21-2012 11:03 PM
Reply to: Message 119 by Bolder-dash
06-21-2012 10:32 PM


Your attempt to make your standard lies and nonsense look remotely relevant to the thread is profoundly unconvincing.

This message is a reply to:
 Message 119 by Bolder-dash, posted 06-21-2012 10:32 PM Bolder-dash has taken no action

  
Newer Topic | Older Topic
Jump to:


Copyright 2001-2018 by EvC Forum, All Rights Reserved

™ Version 4.1
Innovative software from Qwixotic © 2022