Physics Help Forum Work and Energy

 Kinematics and Dynamics Kinematics and Dynamics Physics Help Forum

Apr 7th 2018, 11:19 AM   #11
Junior Member

Join Date: Apr 2018
Posts: 16
 Originally Posted by ChipB It seems to me that all you have doe is decide to create a new type of measurement that has units kg-m/s, and you call it "work." But you don't explain what advantage there is in using this new unit? Does it help us understand the motion of objects in a way that classical mechanics does not? In classical mechanics the definitions of work and energy are useful in helping us calculate the velocity of an object that is subjected to a net force operating over a distance. But your approach doesn't do that, so your approach seems to be of little value. Does it make predictions of an object's motion that are different than Newtonian mechanics would predict, and more importantly - can you demonstrate that your results are more accurate? Also, the concept that a force acting for a period of time (rather than distance) should contribute to "work" falls apart when you consider that multiple forces working on an objects that cancel each other out would lead to the object having infinite "energy." The 20 Kg object resting on a table is constantly subjected the force of gravity, so over time gains an infinite amount of "energy" from gravity. How is that concept useful? How much "energy" does a 2 billion year old rock sitting on the ground have?
First of all did you understand that the joule is the erroneous unit of measure for Work and Energy?

This thing is explainded in detail there.

Last edited by OlegGor; Apr 7th 2018 at 11:28 AM.

Apr 7th 2018, 01:04 PM   #12
Physics Team

Join Date: Jun 2010
Location: Morristown, NJ USA
Posts: 2,280
 Originally Posted by OlegGor First of all did you understand that the joule is the erroneous unit of measure for Work and Energy? If you did not, then please read carefully the 1 link and 2 link. This thing is explainded in detail there.
I did read those links, and no, it's not explained. No where do you actually explain how the classical definition of work is "erroneous" - at best you merely explain how incremental velocity changes occur over time. Nothing new, nor very interesting. In Newtonian mechanics it's simply showing that incremental increases in kinetic energy come about from applying a force for an incremental amount of time. You have not shown that it's erroneous at all.

Apr 7th 2018, 07:10 PM   #13
Junior Member

Join Date: Apr 2018
Posts: 16
 Originally Posted by ChipB I did read those links, and no, it's not explained. No where do you actually explain how the classical definition of work is "erroneous" - at best you merely explain how incremental velocity changes occur over time. Nothing new, nor very interesting. In Newtonian mechanics it's simply showing that incremental increases in kinetic energy come about from applying a force for an incremental amount of time. You have not shown that it's erroneous at all.
Let's go step by step (just some steps).

Step 1
Do you admit that the 2nd seconds in the two processes are completely identical?

Apr 7th 2018, 08:02 PM   #14

Join Date: Apr 2008
Location: On the dance floor, baby!
Posts: 2,238
 Originally Posted by OlegGor Let's go step by step (just some steps). Step 1 Do you admit that the 2nd seconds in the two processes are completely identical?
In both cases we have the same distance function ( $\displaystyle d = v_0t + 4.9t^2$.) They both have the same acceleration and the same initial speed, so yes. This is true for all t.

(Not trying to speak for you, ChipB.)

-Dan

Addendum: With the exception of the forces coming from two distinct kinds of sources.
__________________
Do not meddle in the affairs of dragons for you are crunchy and taste good with ketchup.

See the forum rules here.

Apr 7th 2018, 09:03 PM   #15
Junior Member

Join Date: Apr 2018
Posts: 16
 Originally Posted by topsquark In both cases we have the same distance function ( $\displaystyle d = v_0t + 4.9t^2$.) They both have the same acceleration and the same initial speed, so yes. This is true for all t.
Good.

Step 2.

Do you admit that the Karlson and the gravitational Force are one and the same thing (each one does the same thing with the stone)?

in each process
"there is only one pushing (the Carlson’s pushing in the first case and the pushing of the gravitational Force in the second case) and as a result of this pushing the velocity of the stone (during the 2nd second) increases by 9.8m/s (9.8m/s to 19.6m/s);"

So do you admit that the Karlson and the gravitational Force are one and the same thing (each one does the same thing with the stone)?

Last edited by OlegGor; Apr 8th 2018 at 12:57 AM.

Apr 8th 2018, 04:45 AM   #16

Join Date: Apr 2008
Location: On the dance floor, baby!
Posts: 2,238
 Originally Posted by OlegGor Good. Step 2. Do you admit that the Karlson and the gravitational Force are one and the same thing (each one does the same thing with the stone)? in each process "there is only one pushing (the Carlson’s pushing in the first case and the pushing of the gravitational Force in the second case) and as a result of this pushing the velocity of the stone (during the 2nd second) increases by 9.8m/s (9.8m/s to 19.6m/s);" So do you admit that the Karlson and the gravitational Force are one and the same thing (each one does the same thing with the stone)?
Again, the "objects" have the same initial speed and the same acceleration, so yes, their motions would be the same.

-Dan
__________________
Do not meddle in the affairs of dragons for you are crunchy and taste good with ketchup.

See the forum rules here.

Apr 8th 2018, 05:56 AM   #17
Junior Member

Join Date: Apr 2018
Posts: 16
 Originally Posted by topsquark Again, the "objects" have the same initial speed and the same acceleration, so yes, their motions would be the same. -Dan
I got you that you admited that the Karlson and the gravitational Force are one and the same thing (during the 2nd second).

Good.

Step 3.

Do you admit that Karlson’s Energy (Resource) will not be spent on this Inertial Displacement of the stone (9.8m, during the 2nd second), since the stone moves this 9.8m displacement, during the 2nd second, also by inertia, as during the 1st second.

Apr 8th 2018, 06:17 AM   #18
Physics Team

Join Date: Jun 2010
Location: Morristown, NJ USA
Posts: 2,280
 Originally Posted by topsquark (Not trying to speak for you, ChipB.)
No worries - I'm confident that you and I are on the same page.

 Originally Posted by OlegGor I got you that you admited that the Karlson and the gravitational Force are one and the same thing (during the 2nd second). Good. Step 3. Do you admit that Karlson’s Energy (Resource) will not be spent on this Inertial Displacement of the stone (9.8m, during the 2nd second), since the stone moves this 9.8m displacement, during the 2nd second, also by inertia, as during the 1st second.
I agree that during the 2nd second Karlson's energy is spent on increasing the stone's velocity from 9.8m/s to 19.6 m/s. That's a change of 9.8 m/s, which as the same as the change in velocity during the first second. As for distance covered - Karlson's force during the 2nd second causes the stone to travel 4.9m further than it would have if Karlson's force had become zero at t = 1 second. Is that what you're asking?

I think where we will stop agreeing is when you jump to the conclusion that (quoting from your first linked article ) "now science ERRONEOUSLY THINKS that Karlsson’s Energy (Resource) and the Energy (Resource) of the gravitational Force are spent on the Inertial Displacement of the stone (9.8m, during the 2nd second)." Is that what you're going to say next?

Last edited by ChipB; Apr 8th 2018 at 06:25 AM.

Apr 8th 2018, 06:41 AM   #19
Junior Member

Join Date: Apr 2018
Posts: 16
 Originally Posted by ChipB I agree that during the 2nd second Karlson's energy is spent on increasing the stone's velocity from 9.8m/s to 19.6 m/s. That's a change of 9.8 m/s, which as the same as the change in velocity during the first second. As for distance covered - Karlson's force during the 2nd second causes the stone to travel 4.9m further than it would have if Karlson's force had become zero at t = 1 second. Is that what you're asking? I think where we will stop agreeing is when you jump to the conclusion that (quoting from your first linked article ) "now science ERRONEOUSLY THINKS that Karlsson’s Energy (Resource) and the Energy (Resource) of the gravitational Force are spent on the Inertial Displacement of the stone (9.8m, during the 2nd second)." Is that what you're going to say next?
First of all in order to be clear

Do you admit that the 2nd seconds in these two processes are completely identical?

Do you admit that the Karlson and the gravitational Force are one and the same thing -- each one does the same thing with the stone (during the 2nd second)?

Do you admit that Karlson’s Energy (Resource) will not be spent on this Inertial Displacement of the stone (9.8m, during the 2nd second), since the stone moves this 9.8m displacement, during the 2nd second, also by inertia, as during the 1st second?

Only Yes or No.

Last edited by OlegGor; Apr 8th 2018 at 11:50 AM.

Apr 8th 2018, 09:11 AM   #20

Join Date: Apr 2008
Location: On the dance floor, baby!
Posts: 2,238
 Originally Posted by OlegGor Do you admit that the 2nd seconds in these two processes are completely identical?
Yes. Please read the responses. If nothing changes the motion due to gravity and the motion due to Karl are the same for all time, t.

 Originally Posted by OlegGor Do you admit that the Karl and the gravitational Force are one and the same thing -- each one does the same thing with the stone (during the 2nd second)?
Sort of. Again, so long as the initial velocity and acceleration are the same in both cases the motion will be the same. (Though your language is a bit off... technically speaking the gravitational and the "Karl - tional" accelerations are from two different sources so they are not alike in that way. Though reference General Relativity for a more highbrow explanation where the two concepts are actually the same.)

 Originally Posted by OlegGor Do you admit that Karlson’s Energy (Resource) will not be spent on this Inertial Displacement of the stone (9.8m, during the 2nd second), since the stone moves this 9.8m displacement, during the 2nd second, also by inertia, as during the 1st second?
That depends on what an "Energy Resource" is. Sorry, I'm cranky, tired, achy, feverish and I'm not going to read your article to point out all the flaws. We can do that a lot more simply in the thread. So please define what an energy resource is.

However I can probably say "no." There is no distinction in the motion equations that would separate the two cases at any time. The pertinent equations are the motion in one dimension equations:
$\displaystyle x = x_0 + v_0t + \frac{1}{2}at^2$

$\displaystyle x = x_0 + \left ( \frac{v_0 + v}{2} \right ) t$

$\displaystyle v = v_0 + at$

$\displaystyle v^2 = v_0^2 + 2a(x - x_0)$

All of these equations are identities for all time for both of the motions you are describing. If you are saying otherwise my answer is "No, I do not agree with you."

-Dan
__________________
Do not meddle in the affairs of dragons for you are crunchy and taste good with ketchup.

See the forum rules here.

 Tags energy, physics, work, work and energy

 Thread Tools Display Modes Linear Mode

 Similar Physics Forum Discussions Thread Thread Starter Forum Replies Last Post NSB3 Advanced Mechanics 1 Nov 12th 2014 12:03 PM FlexedCookie Kinematics and Dynamics 4 Mar 15th 2011 02:42 AM reiward Energy and Work 1 Oct 12th 2010 09:01 AM Morgan82 Advanced Mechanics 1 Nov 10th 2008 02:52 AM Inertialforce Energy and Work 1 Oct 31st 2008 07:51 PM