Understanding Work and Energy Transfer: The Relationship and Implications

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Work is defined as the transfer of energy through the application of force over a distance, calculated as the product of force and distance. If no movement occurs, no work is done, leading to the question of energy output despite exertion. Scenarios illustrate that while a person may exert energy without moving an object, the work equation indicates zero output, raising questions about energy conservation. The discussion also touches on gravitational forces, noting that while they exert influence, they do not perform work in the traditional sense as defined by the equation. Ultimately, the conversation emphasizes the need for a deeper understanding of work, energy, and their interrelations in physical systems.
  • #61
This is as far as I got in the thread and it bears repeating:
chroot said:
This is not difficult to understand.

- Warren
This is not difficult to understand. I'm no longer amused and I no longer believe there is any chance you kiddies are making an honest effort here.
 
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  • #62
chronos u can convert from scalar to vector.. and russ we aren't trying to amuse u..
 
  • #63
beatrix kiddo said:
chronos u can convert from scalar to vector.. and russ we aren't trying to amuse u..

why would you do that? I am not sure I follow...? For instance, if you take away the directional component of a force and only have a magnitude of acceleration (times mass) remaining, doesn't that leave you with a push or pull in no direction?

But maybe I don't understand what you mean by "convert". :confused:
 
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  • #64
Math Is Hard said:
why would you do that? I am not sure I follow...? For instance, if you take away the directional component of a force and only have a magnitude of acceleration (times mass) remaining, doesn't that leave you with a push or pull in no direction?

But maybe I don't understand what you mean by "convert". :confused:

When you use the work equation, you multiply by sin(A), which breaks it down to one of the components of the vector. This component is scalar. (You do it all the time when summing vectors)

In essence, multiplying by a trig function tends to remove the vectoriel properties of a vector.

To Urtalkinstupid:
My mistake, it's the multiplication by the angle, not the distance, which makes Work scalar.
 
  • #65
beatrix kiddo said:
...and russ we aren't trying to amuse u..
No, you're probably just trying to amuse yourselves. Regardelss, the only reason you two are still members here is you are amusing to us (except a small possibility others are learning from your mistakes). Our patience, however, has limits.

The concept being explained here is (again) junior high science class simple (and I'm pretty sure I could make an average elementary school student understand it*). Its simply not possible for you two to not be smart enough to understand it. That means you guys are choosing to not understand it. Why, we're not sure, but regardless, you are not making an effort to help yourselves and you are not making a positive contribtion to this board.

*Elementary school analogy: A car stationary at idle does no useful work. All of the energy input by the engine is wasted as heat, either dissipated by the radiator/engine block or blown out the tailpipe.
 
  • #66
urtalkinstupid said:
You can convert scalar to vector and vice versa.

You can get a scalar from a vector (by taking the modulus for example), but you can't get a vector from a scalr without introducing another vector.
 
  • #67
No, you're probably just trying to amuse yourselves. Regardelss, the only reason you two are still members here is you are amusing to us (except a small possibility others are learning from your mistakes). Our patience, however, has limits.

basically u see stupid and me as a couple of clowns here for ur enjoyment... and ur patience is limited... what's going to happen when it runs out? are u going to close this thread down, too?

Its simply not possible for you two to not be smart enough to understand it. That means you guys are choosing to not understand it. Why, we're not sure, but regardless, you are not making an effort to help yourselves and you are not making a positive contribtion to this board.

we choose not to understand?! oh we understand.. we ALL understand...

*Elementary school analogy: A car stationary at idle does no useful work. All of the energy input by the engine is wasted as heat, either dissipated by the radiator/engine block or blown out the tailpipe.

...

You can get a scalar from a vector (by taking the modulus for example), but you can't get a vector from a scalr without introducing another vector.

agreed
 
  • #68
so Energy and Work are related.

Work and energy are the same thing.

E = {{kg} \cdot {m^2}} / {s^2}

W = F \cdot m

and...

F = {{kg} \cdot {m}} / {s^2}

so substitute F and you get...

W = {{kg} \cdot {m}} / {s^2} \cdot m =

{{kg} \cdot {m^2}} / {s^2} = E

Therefore...

E = W
 
  • #69
jcsd said:
You can get a scalar from a vector (by taking the modulus for example), but you can't get a vector from a scalr without introducing another vector.

You use two scalar values and an angle to get a vector. (Unless the components of a vector aren't considered scalar?)

Anyways, it stands to reason that if you can go one way, you can go the other by doing the opposite thing. If multiplying by sin(30) eliminated the vector.. well divide by it... or use arcsin.
 
  • #70
basically u see stupid and me as a couple of clowns here for ur enjoyment... and ur patience is limited... what's going to happen when it runs out? are u going to close this thread down, too?

Errr... More like ban you guys from the board.
 
  • #71
Entropy said:
Errr... More like ban you guys from the board.

A bit off-topic. But yes, you guys are probably going to get banned if you keep up the pace of refusing to believe simple things.

I know this si theory development, but your goal as a physicist should really be to disprove your theory... it's just SO much easier. And if you can't, then you know that your theory is much better for it than if you'd just risked it.
 
  • #72
Errr... More like ban you guys from the board.

But yes, you guys are probably going to get banned if you keep up the pace of refusing to believe simple things.

why would they ban us? i thought chroot told me i could be a mentor... :wink:

but your goal as a physicist should really be to disprove your theory...

why would i do that? I'm trying to prove my theory to u guys... i already know there are some flaws in it, but the current model has flaws too. nonetheless, i am going to continue advocating the push theory because i know it's right.
 
  • #73
beatrix kiddo said:
but the current model has flaws too.
This is false. There are no known experiments that contradict the standard model, or general relativity, over their domains.
nonetheless, i am going to continue advocating the push theory because i know it's right.
You know it's right? How do you know this?

- Warren
 
  • #74
There is actually a good contradiction between SR and GR.
 
  • #75
beatrix kiddo said:
why would they ban us? i thought chroot told me i could be a mentor... :wink:

Because of these types of comments. (Yes, I got it, I know)

beatrix kiddo said:
why would i do that? I'm trying to prove my theory to u guys... i already know there are some flaws in it, but the current model has flaws too. nonetheless, i am going to continue advocating the push theory because i know it's right.

By failing to disprove your theory you accumulate evidence towards it's correctness.

I forget who it was that thought that everything he looked at that was a non-black non-raven accumulated evidence that all ravens were black, but I like that logic.
 
  • #76
urtalkinstupid said:
There is actually a good contradiction between SR and GR.

What a waste of a post. At least tell us what they are instead of looking like you've got nothing more than the words.
 
  • #77
urtalkinstupid said:
There is actually a good contradiction between SR and GR.
SR can be derived from GR. Duh.

- Warren
 
  • #78
Ok, you have the elevator experiment that Einstein used for his equivalence principle.

You have one elevator in space and one elevator on earth. Both are being affected by force, but they are different forces. The one on Earth is experiencing force (acceleration) by gravity at a rate of 9.8m/s^2, while the elevator in space is experiencing accelerated forces at a rate of 9.8m/s^2. So, on earth, the acceleration is 1-g. The elevator in space is being accelerated at 1-g equivalence. Therefore, you are unable to tell if you are moving or stationary, right?

Ok, here is how it contradicts with SR. In space, your velocity increase by the appliance of this 1-g force, while on Earth it is unoticeable. So, in space, time will allow you to reach close to the speed of light. What happens as your velocity increases? Yes, your mass increases as well. So, you are able to tell that you are moving by an increase in mass overtime. Your velocity in space will never reach the speed of light, but it will come ever so close, like an asymptote. So, your mass will increase forever as long as you are experiencing this 1-g in space. Thus, you are able to tell if a force is applied by acceleration or gravity by the fact if your mass is increasing or not. Or something like that.

I'm sure you people will find something wrong with this. Just an idea I saw while trying to get information on SR and GR.
 
  • #79
urtalkinstupid said:
Thus, you are able to tell if a force is applied by acceleration or gravity by the fact if your mass is increasing or not.
The mass of a body in its own rest frame is always its rest-mass. You can't tell you're moving unless you look out the proverbial window.

- Warren
 
  • #80
urtalkinstupid said:
Just an idea I saw while trying to get information on SR and GR.
If you're trying to learn, you should try reading books or reputable journals instead of crackpot websites, I guess.

- Warren
 
  • #81
urtalkinstupid said:
Ok, you have the elevator experiment that Einstein used for his equivalence principle.


You have one elevator in space and one elevator on earth. Both are being affected by force, but they are different forces. The one on Earth is experiencing force (acceleration) by gravity at a rate of 9.8m/s^2, while the elevator in space is experiencing accelerated forces at a rate of 9.8m/s^2. So, on earth, the acceleration is 1-g. The elevator in space is being accelerated at 1-g equivalence. Therefore, you are unable to tell if you are moving or stationary, right?

Ok, here is how it contradicts with SR. In space, your velocity increase by the appliance of this 1-g force, while on Earth it is unoticeable. So, in space, time will allow you to reach close to the speed of light. What happens as your velocity increases? Yes, your mass increases as well. So, you are able to tell that you are moving by an increase in mass overtime. Your velocity in space will never reach the speed of light, but it will come ever so close, like an asymptote. So, your mass will increase forever as long as you are experiencing this 1-g in space. Thus, you are able to tell if a force is applied by acceleration or gravity by the fact if your mass is increasing or not. Or something like that.

I'm sure you people will find something wrong with this. Just an idea I saw while trying to get information on SR and GR.

I feel it coming... here we go again
You are always a rest with yourself (please don't argue about moving your arms). So ACCORDING TO YOU you always have your rest mass. ACCORDING TO YOU you are exerting a slightly smaller force on Random-Person than what he percieves.

Although this sounds impossible, length contraction and time dilation (and probably a few other factors) cancel this out. So reality doesn't shatter or anything.
 
  • #82
Books and journals are boring... :zzz:

Length contraction and time dilation seem odd! I just told you I ran into this. This guy also goes more indepth into how length contraction and time dilation are factors that contradict with GR.

P.S. When I said "Energy and Work are related," I meant "Energy and Force are related."
 
  • #83
Alkatran said:
When you use the work equation, you multiply by sin(A), which breaks it down to one of the components of the vector. This component is scalar. (You do it all the time when summing vectors)

Just a quick question, Alkatran. What is forming the angle A that you are using to for the sin ratio? I never had any trig come up in solving Work problems so I am not quite visualising this. Whenever I have calculated Work done, I've just multiplied force x distance and then specified the result as a scalar quantity (I had learned somewhere that the product of two vector quantities will always be scalar). The other way I've calculated Work done it is to integrate a force function over a distance. No trig involved here either.
What gives? Just curious.
 
  • #84
chroot said:
This is false. There are no known experiments that contradict the standard model, or general relativity, over their domains.

This is false. The standard model does not provide unity among the four fundamental forces. They contradict each other in a sense they are not able to be combined.
 
  • #85
urtalkinstupid said:
This is false. The standard model does not provide unity among the four fundamental forces. They contradict each other in a sense they are not able to be combined.
While it's true that the predictions of GR and QM are incompatible in places such as the insides of black holes, what I said is that are no known experiments contradict either theory, and that is certainly true.

We certainly have more physics left to discover, but there is nothing wrong with the current theories over their respective domains. Any new physics that is discovered will simply be a generalization of these two theories which widens the domain.

- Warren
 
  • #86
urtalkinstupid said:
Books and journals are boring... :zzz:
You can choose a lifetime of ignorance if that's what you want. :shrug:
Length contraction and time dilation seem odd!
So does Mandarin Chinese to a native English speaker.
This guy also goes more indepth into how length contraction and time dilation are factors that contradict with GR.
Who is "this guy?" Whoever he is, I suspect that he's listed on crank.net for being, well, a crank. Don't believe everything you read. For someone who claims to be a free thinker, you sure do seem to get caught up in other people's malformed claims pretty often.

- Warren
 
  • #87
chroot said:
So does Mandarin Chinese to a native English speaker.

Not necessarily. My friend is Taiwanese, and when she speaks Mandarin, it does not sound odd.

This "guy" looks like he's pretty intelligent. I don't have the link rigth now, because I'm in the lab at college doing my summer course in mechanical engineering. :frown:

I love being ignorant. :rolleyes:
 
  • #88
urtalkinstupid said:
Not necessarily. My friend is Taiwanese, and when she speaks Mandarin, it does not sound odd.
You understand my point -- that although time dilation and length contraction seem "odd" or counter-intuitive at first, they are not wrong.
This "guy" looks like he's pretty intelligent. I don't have the link rigth now, because I'm in the lab at college doing my summer course in mechanical engineering. :frown:
If he says that GR and SR are incompatible, he is quite stupid. I'm sorry, but it's easy to show how SR falls out of GR, and anyone with an even cursory understanding of the theories can show it.
I love being ignorant. :rolleyes:
If you eschew books and journals (for whatever reason -- even if they're "boring") and prefer to get your education from crackpots on the internet, you are choosing ignorance.

- Warren
 
  • #89
chroot said:
If you eschew books and journals (for whatever reason -- even if they're "boring") and prefer to get your education from crackpots on the internet, you are choosing ignorance.

At least their babbling is interesting. Books and journals written by scientists are insipid. The same thing everytime you read them. First, they give you a jist of what they are explaining (abstract I guess). Then, they go into experimental evidence. Then, you have observations. Finally, you have a linking between observations and experiments. BORING!
 
  • #90
urtalkinstupid said:
At least their babbling is interesting. Books and journals written by scientists are insipid. The same thing everytime you read them. First, they give you a jist of what they are explaining (abstract I guess). Then, they go into experimental evidence. Then, you have observations. Finally, you have a linking between observations and experiments. BORING!

You're a science fiction fan, yes? Because from what I just read you PREFER reading about theories that are proposed incorrectly (aka, the ones that are most likely to be wrong).
 

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