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Has Physical Work To Be Done, To Move A Mass In A Horizontal Direction ?

physical work

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#1 deschoe

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Posted 01 March 2017 - 08:13 AM

here the question according to http://www.sciencefo...ome-from/page-8 .

 

you see a book on a table, that is accelerated and decelerated by springs. these book was moved in a horizontal direction and farming guy, ocean breeze and exchemist claim, physical work was done, even if one neglect friction. 

 

cache_2471211969.png?t=1488051256

 

 you can see that on the left picture you have a book motionless lying there, and one tentioned spring and one  relaxed spring, after moving the book, in the picture on the right site you have a horizontal moved book that is motionless lying there and again one tentioned spring and one  relaxed spring. still any questions ?

 

that shows I think , that horizontal movement doesnt mean physical work is done., and ex, farming and breeze know exactly, why they refuse to make the calculation, because otherwise they have to admit, that their theory is nonsens.

 

so the question, who is right, me or these three guys ?


Edited by deschoe, 01 March 2017 - 05:15 PM.


#2 CraigD

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Posted 01 March 2017 - 04:16 PM

The mechanics here are straightforward.

Let’s say:
Each spring produced a constant 1 N force while extending,
and extends 1 m toward the center of the table.

The work done when the spring extends, then, is 1 N x 1 m = 1 J.

Note that we don’t need to know the book’s mass, and only need to know that the force of the spring is sufficient to move the book. We don’t need to know the force of friction of the book on the table.

If we assume zero frictional forces, then the book will move forever. Each time a spring is compressed, 1 J of work is done. Each time it is extended, 1 J of work is done. The book+table+springs constitute a perpetual motion machine of the third kind.

#3 deschoe

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Posted 01 March 2017 - 04:58 PM

@D

 

thank you



#4 deschoe

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Posted 01 March 2017 - 06:13 PM

@D

 

would you please be so kind and explain  farming guy, that horizontal movement means no physical work is done ( by neglecting fricton ). because he thinks your statement says something different ( quotation : Posted Today, 12:00 AM

Did you not read the answer to which you refer above?  I suggest that you read it again, and visit the link that Craig posted. ) http://www.sciencefo...-from/?p=345006

 

and also  pzkpfw paraphrase, your statement says that you have to perfom mechanical work ( which has a negative effect on the energy balance ) to move mass in horizontal direction according to the upper example.

 

 

and of course, the spring performs work, but the other spring "catches" this work.   the question is ,do you have to perfom mechanical work ( which has a negative effect on the energy balance ) moving mass in horizontal direction according to the upper example. exactly, what does this moving ( acceleration + deceleration ) mean for the energy balance ? 

 

 

I think you should determine unconditionally  what is the matter


Edited by deschoe, 02 March 2017 - 09:04 AM.


#5 deschoe

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Posted 03 March 2017 - 05:40 PM

obviously the cat has got the tongues of CraigD, exchemist, farming guy, pzkpfw and ocean breeze, so I want to determine for other readers, that moving a mass in a horizontal direction ( acceleration + deceleration of the mass ) means no physical work was done according to the correspondingly energy balance, as I claimed, and the claims of exchemist, farming guy, pzkpfw and ocean breeze means nothing else than spreading nonsens inhere and especially CraigD hasnt the courage to admit this.

 

_>   http://www.sciencefo...e-8#entry345063


Edited by deschoe, 03 March 2017 - 05:43 PM.