[Archive!] Pure mathematics, physics, chemistry, etc.: brain-training problems not related to trade in any way - page 76

 
vegetate >>:


вариант 2: напарника нет. С горя откусываем палец и кидаем впереди себя.



))

I'm picturing the finish line in the 100-metre dash.

everyone's throwing something.

 
Mischek >>:


))

Представил себе финиш на стометровке

все что-то кидают

It's just that there was no precedent for a "split runner" %). They will start making amendments to the rules, like "the percentage of the initial body needed to make the finish count" :)

 

to Candid, Mathemat, Yurixx,

A bit more about planes (and it will probably be possible to forget about them by now). Found it by accident. The task is really incorrect, which I tried to tell you about, but I got as far as "hit-and-run" :o). Here in a very concise form it contains all possible ways of interpreting conditions and corresponding conclusions. And all of them are correct in their "incorrectness" :o)

http://dic.academic.ru/dic.nsf/ruwiki/679569

 

Yeah, thanks, Sergei. Good overview.

 
Farnsworth писал(а) >>

to Candid, Mathemat, Yurixx,

A bit more about planes (and it will probably be possible to forget about them by now). Found it by accident. The problem is really incorrect, which I tried to tell you about, but I got as far as

Sergey, can you quote the condition, highlighting what you consider incorrect?

 

...Yeah, and we'll set the right answers by voting.

All right, I get the hint, I'm out.

 
Farnsworth >>:

to Candid, Mathemat, Yurixx,

Еще немного о самолетах (и уже наверное будет можно о них забыть). Нашел случайно. Задача действительно некорректна, о чем пытался и сказать, но довыпендривался до "наездов" :о). Вот тут в очень лаконичной форме собраны все возможные варианты трактовок условий и соответствующих выводов. И все они правильные в рамках своей "неправильности" :о)

http://dic.academic.ru/dic.nsf/ruwiki/679569



Typical mistakes when solving a problem

Mistake 1. "It is intuitively clear, but I would like to hear it explicitly..."
The main mistake is to solve the problem with absolute seriousness, as if you are faced not with a school problem with a deliriously formulated condition, but with a complex scientific problem.

Mistake 2. The problem is formulated incorrectly, which means that the plane won't take off.
"Incorrect problem condition" is not a magic spell against the take-off of a real plane.

Error 3. The problem is incorrectly formulated, so it is impossible to solve it.
It does not "mean" at all. It is physics, not mathematics.

Mistake 4. I don't have enough data to solve the problem.
On the contrary - there is too much data.

Mistake 5. It does not take into account the mass of the wheels, non-linearity of the friction force in the bearings, possible gyroscope effect ...
This is a simple verbal problem to test your intelligence and common sense, not a doctoral dissertation. Don't get lost in thought.

Mistake 6. Everything depends on the atleodchik.
Also, it is correct, but it is not a solution.

Mistake 7. Under certain conditions, the plane will take off, and under certain conditions, it will not take off.
An attempt to pass off your everyday wisdom and life experience as knowledge of physics. You'd better show us what you can do as a physicist.

http://www.abitura.com/problems/aeroplane.htm

 
Farnsworth писал(а) >>

to Candid, Mathemat, Yurixx,

A little more about planes......

Farnsworth, absolutely any problem can be called incorrect.It is impossible to specify all the conditions, and there is no need to. If you specify them, the text of the problem will greatly increase and the problem itself will be complicated and uninteresting.

 
One more thing. About the friction force of the wheels. Why are we even talking about it? How does the friction force in wheel bearings change depending on where the aircraft is standing or moving: on a concrete runway, aircraft carrier steel, asphalt or rubber band. It doesn't. The friction force in wheel bearings should not be confused with the friction force of the wheels' tyres on the pavement, they are different things.
 

Mischek, where are you going? You're the only one who keeps this thread going...

P.S. I deleted my stupid remark, which could be taken as a rebuke (it wasn't).