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Russian/American hills

ValeryOchkov
24-Ruby IV

Russian/American hills

People in America say that it is Russian slides (hills - roller coasters). People in Russia say it's a American hills. Do you know which physical device is described graphically here?

RA-hills.png

22 REPLIES 22

I give it a try. I got limited vision which at any given time is related to my very recent history at most a year.

 

You asked for a device. I could not fit a capacitor in it. Then I said maybe a hydro dam.

 

With the water level dropping the PE drops. With the drop in water level height, the acceleration of the water flow thru the turbines drops, so a velocity drop, that's a KE drop. 

 

Sum of PE+KE can be assumed for the total energy of the dam.

 

The device is a hydro dam. 

 

Yes, good luck Karl !

 

 

 

 

N/A.

I would say a mass-spring system with friction.

KarlBogha
12-Amethyst
(To:DJF)

Emm,

 

I would not have guessed that answer. Maybe if I seen the oscillation between the positive and negative side of the time (x-axis). But it don't have to be set up that way on the plot.

 

Discussion sake, why did a hydro dam not make it?

a). fluctuations with respect to time? Hey rain does that but the time interval is too close? Emm....

b). gradually decline to zero? Happens to dams...many had shut down lack of upstream supply...climate case.

c). not really a device rather a large system for the dam? True, but specific to water level may fit.

d). ......is this a trick? And why not?

 

I am more upset that I did not get it than the reasons a) b) c)... I provided.

Ok so its a R L C circuit? Yes?

No again, well if you must a mass spring damper.

 

 

 

Cheers,

Karl.

 

 

 

 

 

 

 

 

 

N/A.

Karl wrote:

 

Discussion sake, why did a hydro dam not make it?

Well, a dam (nice try, BTW) isn't oscillating.  A harmonic oscillator transfers energy from kinetic to potential and back.  Your dam has both energies but they don't trade, they both degrade--the water level drops to decrease the potential AND that drops the water flow which lowers the kinetic. . .

a). fluctuations with respect to time? Hey rain does that but the time interval is too close? Emm....But rainfall isn't terribly periodic.

b). gradually decline to zero? Happens to dams...many had shut down lack of upstream supply...climate case.

c). not really a device rather a large system for the dam? True, but specific to water level may fit.

d). ......is this a trick? And why not?  No trick!  A lot of systems behave like this.

 

I am more upset that I did not get it than the reasons a) b) c)... I provided.

Ok so its a R L C circuit? Yes?

YES!  An R L C circuit is a harmonic system!  So is a pendulum.  A weight on a spring.  The rotor of a helicopter, The unbalanced wheel on your car.  

No again, well if you must a mass spring damper.  Just because that was most familiar to me.

Who will give me the correct answer to a simple question - for what purpose is a dam being built on a river to generate electricity? If you tell me that in order to create a pressure drop in front of a hydraulic turbine, then I will say that this is the wrong answer. The correct answer is found in the problem of a damped pendulum.

To raise the level of the water, there-by increasing the moment of inertia of the earth and slowing down its rotation so we get more sunlight per day to generate more solar electricity.

ValeryOchkov
24-Ruby IV
(To:DJF)

In order to reduce the speed of water flow in the river. At the same time, losses due to friction of water on the river bottom are reduced, the released energy is converted into electricity.

Emm...

N/A.
KarlBogha
12-Amethyst
(To:DJF)

Ha ha.

N/A.

Duh!

 

A damped spring-mass that has been displaced and released.  AKA harmonic oscillator.

Fred_Kohlhepp_0-1607660839238.png

 

One more picture

osc.png

I'll guess, a helical spring with a mass a the bottom.

Key here is angle displacement versus speed.

Hmm?

 

Not this time. I seen something like a Nyquist diagram in controls.....or was it Locus......

Fail. 

 

N/A.

Solution without animation is not solution!

osc.gif

Sankt-Peterburg! 

RusHills.png

Fred,

 

I received a PDF file from Valery today. Translated it in Google.

File attached. You may be interested in reading relevant pages of the file.

You may scroll down and pick up the Russian PDF file, and use another translator.

You're welcome to comment on the file content.

 

Regards,

Karl.

N/A.

Thank, Karl!

Hi Valery,

 

You came to mind a few months ago. I was so occupied with my own things that is why I had not written.

So much has happened since we last communicated on spring, rlc circuit, hydro dam,....ha ha ha.

I guess Fred Kohlhepp and others feel the same way.

 

In early 2022 things got more political, geographical, ideology, energy,... all stemming from Ukraine crisis.

 

I hope you're doing well. 

 

Kind Regards,

Karl.

N/A.

What has changed for me personally? With my students, I should not use Mathcad, but SMath in the classroom.

I, the son of a Ukrainian mother and a Russian father, who, as a child, was sent to the city of Mariupol on vacation in the summer to swim in the sea, where my grandmother lived, two aunts and one uncle, plus seven cousins, could not dream in a terrible dream that, what happened there.

In my declining years, I began to write memoirs and describe my attitude to many phenomena of life. Look at here. In Russian, but easy to translate into English.

EEE-2-2022-My-Energy.pdf (mpei.ac.ru)

One part

There is such a profession - to cut the budget of the Motherland!
Tell you what it's all about.
One of the sad results of the Second World War was the creation of military industrial complexes in the West and in the USSR.
In theory, after the war, it should have been minimized. But! Representatives of the VVK both in our country and in they did not want to go to the labor exchange to get a job as a security guard in a store or bouncers in a nightclub, for example. They are already accustomed to tossing huge resources ...
These days, real threats hang over the world - coronavirus, global change climate, migration, etc. Half of the world's population is starving, while the other half is overeating and even with fat is furious. Two thirds of the world's population do not have access to clean water. Everything is crap rubbish.
In theory, all funds should be redirected to solving these problems. But the military and the military industry in our country and in their country were frightened of this and deliberately began to escalate the situation in the world.
Our military and theirs and politicians working for the military exchanged winks and smiles to each other like augurs. They do not want to be dragged away from the budget fat feeder and forced to deal with real, not artificially created world problems.
Entire countries have been made victims of this rather vile policy - Syria, Libya, Ukraine, Iran, Iraq, Afghanistan...

 

Valery,

 

Thanks for the PDF file. I had it translated.🤔

 

I read the first few pages. It's interesting about your high school days.🤠

Will read more on this later. I did forward a translation to Fred.👍

 

It was surprising for me to read you've got a full dose of Soviet life thru your career.👨‍🔧

 

 

Kind Regards,

Karl.

 

N/A.

>I had it translated

Send me please.

It is a place where I was born

www.twt.mpei.ac.ru/ochkov/barak.html

Sorri! Ai niid transleition not google-transleition.

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