But 19 in a circle still leads to gridlock.

I agree, but I was laughing at pompous politicalness not Americans, and I thank you for drawing that similar example to my attention.

Stupidity is stupidity, wherever you find it.

 

You're all looking at it wrong.

Imagine it in 3D with some gears lower than others and it works!

 

But 19 in a circle still leads to gridlock.

Which is why KJ6EAD said, "Even if the gear train had had one more or less gear...."

 

A linear arrangement of an odd number of gears is locked. To turn, it would have to have an equal number of gears turning clockwise as counter-clockwise. Even without that problem, the forces required to turn would be enormous, especially at each of the eight occurences of a larger gear trying to turn a smaller one, then there's the ratio problem, where the last gear in the train wants to drive the first but may not be able to if their speeds don't match.

I didn't look closely enough at the coin to see if the number of teeth on each gear can be determined. If so, then it might be interesting to see which single gear could be removed, if any, that would let the resulting ring of 18 gears work.

 

especially at each of the eight occurences of a larger gear trying to turn a smaller one, then there's the ratio problem, where the last gear in the train wants to drive the first but may not be able to if their speeds don't match.

Nope. As long as all the gears are on the same plane and have the same tooth pitch size of the gears and tooth count is irrelevant.

Try doing the math for any even number of gears and their respective ratios to each other how many teeth are on each individual gear and no matter how you do it they will always match tooth to tooth meshing speeds at the end.

 

Nope. As long as all the gears are on the same plane and have the same tooth pitch size of the gears and tooth count is irrelevant.

Try doing the math for any even number of gears and their respective ratios to each other how many teeth are on each individual gear and no matter how you do it they will always match tooth to tooth meshing speeds at the end.

Yep, you're right.

The linear speed of the rim of any two gears has to be the same regardless of the size of the gear (this is what causes the rotational speed to be ratiometric with the diameter of the gear). This is a transitive property and so the linear speed of the rim of ALL the gears has to be the same regardless of the sizes of ANY of the gears. Simple, but somewhat non-intuitive.

So someone that recognizes this would be able to answer my problem in Post #44 trivially. But I bet a bunch of people would spend a bunch of time cranking it by brute force and some of them would see the light at some point -- but many probably would not.

 

Nope. As long as all the gears are on the same plane and have the same tooth pitch size of the gears and tooth count is irrelevant.

Try doing the math for any even number of gears and their respective ratios to each other how many teeth are on each individual gear and no matter how you do it they will always match tooth to tooth meshing speeds at the end.

I agree; I couldn't see from a Mechanical reason why they wouldn't turn; it's all about who wants to be the driving gear. At least 2 of the gears will rotate counter clockwise given any of the 3 gears that want to be a clockwise rotating gear. Of course if they all want to be the drive gear now you have a lock up and some smoking motors. lol



kv

 

Yep, you're right.

The linear speed of the rim of any two gears has to be the same regardless of the size of the gear (this is what causes the rotational speed to be ratiometric with the diameter of the gear). This is a transitive property and so the linear speed of the rim of ALL the gears has to be the same regardless of the sizes of ANY of the gears. Simple, but somewhat non-intuitive.

So someone that recognizes this would be able to answer my problem in Post #44 trivially. But I bet a bunch of people would spend a bunch of time cranking it by brute force and some of them would see the light at some point -- but many probably would not.

All I can see is a loose fitting gear at the bottom; the teeth are not firm. Small gear; smaller teeth and slightly offset.

 

Pick one and turn it either clockwise or counter clockwise ... the remaining two gears will turn in the opposite direction, as they should. However, the illustration of all members of the education team working towards a common goal, I find it humorous that two of three entities would not be in sync with the movement of clockwise or counter-clockwise. there will always be two in opposition of what the third is doing. A dysfunctional operation in moving towards the desired goal.

 

Pick one and turn it either clockwise or counter clockwise ... the remaining two gears will turn in the opposite direction, as they should. However, the illustration of all members of the education team working towards a common goal, I find it humorous that two of three entities would not be in sync with the movement of clockwise or counter-clockwise. there will always be two in opposition of what the third is doing. A dysfunctional operation in moving towards the desired goal.

Even more to the point, though, is that none of the entities will move at all. They are completely bound up and at loggerheads.

 

So, what are we complaining about? We have a dysfunctional education system and this poster is a product of it. Enough said. The king has no clothes.

 

Sums it up nicely, Les.

Edit

It would appear that professors of economics now teach engineering



http://books.simonandschuster.com/The-Perfect-Engine/Patricia-E-Moody/9781451640854

 

It's bigger than that. Try a poll of your non-tech friends, if you have any. My prediction is that many will see no problem and, the thing that bothers me more, some of the people that see the problem won't care.

 

I don't think it gets any bigger wayne.

(Good) engineering comes from attention to detail.
The examples given show a complete disregard for detail.

Worse they are authored by non experts in the subject.
I for instance am non expert in the most popular sport in th UK - angling.
If I wanted a front cover/advert/message to do with say fly fishing I would seek an expert to get it right for me.

 

kv

Edit: Pay attention to the segment of the video 2:34sec. If you decide not to watch all of the video.

Edit: I guess I didn't see "strantor's" post on the toy gears. But; the gears turning in the same direction concept is interesting. Each must posses a driving force together.

 

I'm surprised any two economists have written a book considering you can lay all the economists end to end and never reach a conclusion.

That cover reminds me of government in action. In that sentence you can either leave the space between the last two words or close it. Combined with that cover, its a good descriptor, close the space and it's the results.

 

I'm surprised any two economists have written a book considering you can lay all the economists end to end and never reach a conclusion.

Unless two of those economists are Walter Williams and Thomas Sowell, in which case you'll reach the correct conclusion twice.

 

The Secrist fallacy was one of the biggest mathematical cockups of twentieth century economics.

 

If the real meaning in the gears image like this, the students was the big gears, so they must be the power source , the big gears driving the middle gears as teachers, but the middle gears can't do any movement because the small gears as parents was locked.

Do the students of USA really can handle everything in school or to driving something?

There is no way to do in Taiwan, you can say that the policy came from government to school to teachers and to students and parents.

Public school students in the US have practically no input on curricula or policy, which is just fine with almost all of them.

I remember once when I was staying in Taipei city that a Taiwanese friend and business associate came to me and asked a favor. My hotel (Howard Plaza) was apparently close to where his son was taking an all-day placement test for determining where he would go to college. There was a break in the test during midday, and my friend asked if his son could come to my hotel room to rest, eat, and cool off. I agreed, and allowed the friend, his son, and his wife to have my room for the day. The boy did well, and my friend explained how important that test was for the son and would largely determine how he would spend the rest of his life. I came to understand how seriously most Taiwanese take public schooling.

 

My wife, who's from Taiwan, has described how serious they take those tests and how much they determine your path from that point on.

There are some things I have always liked about the U.S. system and I would hate to see go away, but those things that I like have been pretty badly bastardized over the years. I like that students have the freedom to pursue what interests them and have the ability to change gears. What I don't like is the degree we've succumbed to this notion that all programs have to be "equally accessible" to all students, regardless of how well prepared they may or may not be. I was very fortunate (well, it was more than just luck as my parents made sacrifices to move us to a good school district) to go to a high school in a district that had its act largely together. They recognized that some students were headed to college and that other students weren't and they did a good job of providing good options for both groups. You could graduate from high school with a whole slew of AP courses behind you or you could graduate as a licensed welder or a licensed cosmetologist. The trades programs were not only very good, they were very competitive to get into. And that was in addition to having programs specifically for students that were teen mothers. The provided all of this at reasonable property tax rates and had pretty low dropout rates and very good success from nearly all of the programs. But it was also the case that students from one program didn't mingle a whole lot with students from other programs, both because the programs were pretty heavily fleshed out and didn't leave much opportunity to take classes in other programs, but also because students just naturally hang out with other students that are in the same program and have the same interests. A few years after I graduated the forces came into play to "mainstream" everyone and make all programs "accessible" to everyone. Within a few years all of the trades programs were gone as were most of the AP courses. The quality of the education for everyone tanked -- but everybody was more "equal".