simple logic tells me gravity is not conservative!
Moderator: scott
re: simple logic tells me gravity is not conservative!
Try turning the problem upside down - a pendulum let swing from 3 o'cl to 9 o'cl - with a pulse force at 6 o'cl ? It swings past 9 o'cl & gains more PE - is this greater than the pulse force energy you gave it ?
re: simple logic tells me gravity is not conservative!
Ok yes, good point flecher, we will turn this table upside down.
this side of the story is almost easier to explain.
a weight will drop from 3:00 and travel clockwise to 9:00
all forces balance here. weight will arrive at 9:00 with same velocity it started with at 3:00.
OK now lets give mass a kick in the a$$ at 6:00 after it's fall from 3:00
what happens now is extra horizontal velocity is obtained at 6:00 which is then carried through to become extra vertical velocity at 9:00.
gravity weakens the force of the weight moving upwards at this extra velocity at 9:00
So you have actually lost energy due to gravity with this push at 6:00
the weight traveling upwards at 9:00 carries less force than the force of your push at 6:00
gravity works against your push..
this model is an energy robber.
gravity can either have a negative or positive influence on the force of moving weights.
this side of the story is almost easier to explain.
a weight will drop from 3:00 and travel clockwise to 9:00
all forces balance here. weight will arrive at 9:00 with same velocity it started with at 3:00.
OK now lets give mass a kick in the a$$ at 6:00 after it's fall from 3:00
what happens now is extra horizontal velocity is obtained at 6:00 which is then carried through to become extra vertical velocity at 9:00.
gravity weakens the force of the weight moving upwards at this extra velocity at 9:00
So you have actually lost energy due to gravity with this push at 6:00
the weight traveling upwards at 9:00 carries less force than the force of your push at 6:00
gravity works against your push..
this model is an energy robber.
gravity can either have a negative or positive influence on the force of moving weights.
re: simple logic tells me gravity is not conservative!
hmmm .. I beg to differ Arthur - you would have lots of areas of interest with Itseung888 & Milkovic.
Assuming no system losses the pendulum is let go at 3 o'cl - it accelerates under the influence of gravity until it reaches 6 o'cl - btw, it has the same velocity & KE it would have had had it been just an isolated weight dropped vertically from the same height, only the act of turning it 1/4 turn via Centripetal Force [Cp] makes it take longer to acquire this KE.
With no additional pulse force at this stage the pendulum would continue to climb upwards due to inertia with the acceleration of gravity working against it now i.e. momentum would continue the swing with gravity now acting against it so depleting the momentum until the pendulum came to a stop at 9 o'cl [same PE as it started with].
This time we give it a pulse - the pendulum gets extra momentum & gravity acts the same as the previous example - now the pendulum rises above 9 o'cl [lets say 10 o'cl] until is momentum is reduced to zero & it has no KE again - if we latch it there at the instant it stopped moving we could now calculate its new PE = mgh - if we were to let the pendulum go & fall down to 9 o'cl again it would accelerate under gravity as usual & has a measure of KE at 9 o'cl [if we abruptly stop it there] - if measured the KE regained would exactly equal the pulse energy we gave it to get it to rise to 10 o'cl in the first instance.
Assuming no system losses the pendulum is let go at 3 o'cl - it accelerates under the influence of gravity until it reaches 6 o'cl - btw, it has the same velocity & KE it would have had had it been just an isolated weight dropped vertically from the same height, only the act of turning it 1/4 turn via Centripetal Force [Cp] makes it take longer to acquire this KE.
With no additional pulse force at this stage the pendulum would continue to climb upwards due to inertia with the acceleration of gravity working against it now i.e. momentum would continue the swing with gravity now acting against it so depleting the momentum until the pendulum came to a stop at 9 o'cl [same PE as it started with].
This time we give it a pulse - the pendulum gets extra momentum & gravity acts the same as the previous example - now the pendulum rises above 9 o'cl [lets say 10 o'cl] until is momentum is reduced to zero & it has no KE again - if we latch it there at the instant it stopped moving we could now calculate its new PE = mgh - if we were to let the pendulum go & fall down to 9 o'cl again it would accelerate under gravity as usual & has a measure of KE at 9 o'cl [if we abruptly stop it there] - if measured the KE regained would exactly equal the pulse energy we gave it to get it to rise to 10 o'cl in the first instance.
re: simple logic tells me gravity is not conservative!
regarding this pendulum activity:
weight (w) is released from 3:00 position and drops to 6:00.
a force is added to weight (w) just at 6:00.
this force causes weight (w) at 6:00 to take on an added horizontal velocity of 1mph.
weight (w) reaches 9:00 traveling 1mph upwards.
the force that added 1mph to the horizontal velocity of weight (w) at 6:00 -
- is the same as the force of weight (w) traveling horizontally at 1mph.
this force is greater than the force of weight (w) at 9:00 traveling 1 mph upwards.
because gravity is working against the force of weight (w) at 9:00.
the difference in forces is the difference between:
the force of weight (w) traveling 1 mph horizontally
vs.
the force of weight (w) traveling 1 mph upwards.
force is applied horizontally, this force shifts upwards, losing power to gravity.
weight (w) is released from 3:00 position and drops to 6:00.
a force is added to weight (w) just at 6:00.
this force causes weight (w) at 6:00 to take on an added horizontal velocity of 1mph.
weight (w) reaches 9:00 traveling 1mph upwards.
the force that added 1mph to the horizontal velocity of weight (w) at 6:00 -
- is the same as the force of weight (w) traveling horizontally at 1mph.
this force is greater than the force of weight (w) at 9:00 traveling 1 mph upwards.
because gravity is working against the force of weight (w) at 9:00.
the difference in forces is the difference between:
the force of weight (w) traveling 1 mph horizontally
vs.
the force of weight (w) traveling 1 mph upwards.
force is applied horizontally, this force shifts upwards, losing power to gravity.
Last edited by arthur on Wed Sep 12, 2007 7:53 am, edited 11 times in total.
re: simple logic tells me gravity is not conservative!
It all goes back to the burning question:
..........IS THIS NOT TRUE?
A weight traveling at a velocity (x):
- has less force when traveling upwards
- more force when traveling downwards.
..........IS THIS NOT TRUE?
A weight traveling at a velocity (x):
- has less force when traveling upwards
- more force when traveling downwards.
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Georg Künstler
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re: simple logic tells me gravity is not conservative!
Hi Arthur,
you wrote
But regardless, even if you rob energy from one side of the wheel, it will be unbalanced.
The question is, how to repeat this function, not only a one shot. If you can repeat it, you have won.
Maybe teeter tauter on this board is interresting for you. You have an up and down of the weights and also a side shift. Forces on the ground will variate by rolling.
the future has begun
Georg
you wrote
if some models robber energy, somewhere the robbed energy must be. The other system must have the energy.this model is an energy robber.
But regardless, even if you rob energy from one side of the wheel, it will be unbalanced.
The question is, how to repeat this function, not only a one shot. If you can repeat it, you have won.
Maybe teeter tauter on this board is interresting for you. You have an up and down of the weights and also a side shift. Forces on the ground will variate by rolling.
the future has begun
Georg
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psychopath
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re: simple logic tells me gravity is not conservative!
Arthur, I understand completely your point. I also disagree, but I cannot think of anyway of explaining to you why this wont work. Unfortunately it is not down to your two axioms. There is simply more to it.
Someone with a good understanding of physics should clearly explain why this wont work, not just in two words but logically disprove it. You seem so completely certain, there is no way to convince you without a good explanation.
By the way, I do believe that gravity might not be conservative, but your argument fails to prove this. If you are 100 percent certain of this, then build an experiment. Make it simple and obvious.
Someone with a good understanding of physics should clearly explain why this wont work, not just in two words but logically disprove it. You seem so completely certain, there is no way to convince you without a good explanation.
By the way, I do believe that gravity might not be conservative, but your argument fails to prove this. If you are 100 percent certain of this, then build an experiment. Make it simple and obvious.
Re: re: simple logic tells me gravity is not conservative!
I think psychopath makes a valid point - head to the garage & grab a bike & attach a weight - use a spring balance fish scale if you like to give it an extra pull & see what happens - the analogy is a boy tapping a hoop.arthur wrote:It all goes back to the burning question:
..........IS THIS NOT TRUE?
A weight traveling at a velocity (x):
- has less force when traveling upwards
- more force when traveling downwards.
A weight traveling at velocity X has the same ENERGY [Kinetic Energy] regardless of what direction it is traveling - to slow this momentum to a stop will require an equal amount of Energy acting against it as it took to get it up to speed - otherwise I'm completely misreading you here. When the weight is rising or falling in a gravity field the force of gravity continues to act on the weight [but its acceleration is always straight down] so it is either adding to or subtracting from the velocity.
P.S. I started to model this up on wm2d but then thought you wouldn't buy that either ;) [actually it got hard to represent the forces that would have made sense to anyone who didn't use the program & I know how you don't like pictures]
re: simple logic tells me gravity is not conservative!
I'm sure that most of you people can see my logic by now even if you don't believe it is true.
If this logic is correct it clearly shows that gravity can be used as a source of energy.
A weight (w) traveling at a velocity (x):
- has less force when traveling upwards
- more force when traveling downwards.
there is a discrepancy here between the forces of this weight moving at the same velocity -
- this discrepancy is due to gravity.
my 9:00/3:00 'models' represent this logic.
force (x) moves weight (w) on a path from point A to point B.
there is no vertical distance between point A and point B.
On this journey from point A to point B it is possible for weight (w) to achieve a greater force than force (x) -
- thanks to gravity.
so of course I try to think for myself sometimes.
I might not submit to an opposing statement that can't be well explained.
Such as: "you are wrong" or "hundreds of years of careful testing proves that you are wrong".
because I know that bessler's gravity wheel was for real.
hundreds of years of careful testing cannot prove that gravity is a conservative force or that bessler was a fraud.
I also know that hundreds of years of careful disinformation has brainwashed the submissive public into believing that you need to buy gas and pay for electricity.
If this logic is correct it clearly shows that gravity can be used as a source of energy.
A weight (w) traveling at a velocity (x):
- has less force when traveling upwards
- more force when traveling downwards.
there is a discrepancy here between the forces of this weight moving at the same velocity -
- this discrepancy is due to gravity.
my 9:00/3:00 'models' represent this logic.
force (x) moves weight (w) on a path from point A to point B.
there is no vertical distance between point A and point B.
On this journey from point A to point B it is possible for weight (w) to achieve a greater force than force (x) -
- thanks to gravity.
so of course I try to think for myself sometimes.
I might not submit to an opposing statement that can't be well explained.
Such as: "you are wrong" or "hundreds of years of careful testing proves that you are wrong".
because I know that bessler's gravity wheel was for real.
hundreds of years of careful testing cannot prove that gravity is a conservative force or that bessler was a fraud.
I also know that hundreds of years of careful disinformation has brainwashed the submissive public into believing that you need to buy gas and pay for electricity.
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LustInBlack
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re: simple logic tells me gravity is not conservative!
Instead of asking why it's not true, tell us WHY IT IS TRUE!
You are like a child with 100 pennies that don't want to trade a hundred dollars in paper because it looks like there are much more value to the pennies because of the number of them ..
Sum of the parts..
I've been playing with these things enough to know what you talk about and I've been there too, but I understood by experimenting, nobody is going to put the mashed food in your mouth..
You are like a child with 100 pennies that don't want to trade a hundred dollars in paper because it looks like there are much more value to the pennies because of the number of them ..
Sum of the parts..
I've been playing with these things enough to know what you talk about and I've been there too, but I understood by experimenting, nobody is going to put the mashed food in your mouth..
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John Collins
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re: simple logic tells me gravity is not conservative!
I am for once on the side of the mainstreamers Arthur, in part at least. In my opinion gravity has to be a conservative force otherwise we cannot use it in the way we want to - those of us who believe in a solely gravity-powered wheel, because non-conservative forces do not store energy and are dissipative. If they cannot store energy then you cannot use potential energy because they don't have any.
John
John
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LustInBlack
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re: simple logic tells me gravity is not conservative!
Missread the John post..
...
...
re: simple logic tells me gravity is not conservative!
What the hell - I had built it anyway - knock yourself out.
The weight is 1 kg - the pulse force is 50 Newtons for 8/100ths of a sec - the weight swings up then shot 5 is how far it goes back the other way - no losses in the system.
The Pulse Force is made using an IF statement inside an IF statement for those who want to know how to turn it on & off.
The weight is 1 kg - the pulse force is 50 Newtons for 8/100ths of a sec - the weight swings up then shot 5 is how far it goes back the other way - no losses in the system.
The Pulse Force is made using an IF statement inside an IF statement for those who want to know how to turn it on & off.
- Attachments
-
- Start position release 3 o'cl
-
- Pulse turns on
-
- Just as Pulse Force turns off - 50N for 8/100ths sec
-
- New height achieved
-
- After the swing back from new height
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- PulseForce01.wm2d
- Pulsed Pendulum
- (7.29 KiB) Downloaded 326 times
re: simple logic tells me gravity is not conservative!
the force of weight (w) moving at 2 mph horizontallyInstead of asking why it's not true, tell us WHY IT IS TRUE!
=
the force required to decelerate weight (w) from 2 mph horizontally to 0 mph
=
the force required to accelerate weight (w) from 0 mph to 2 mph horizontally.
likewise,
the force of weight (w) moving at 2 mph downward
=
the force required to decelerate weight (w) from 2 mph downwards to 0 mph
=
the force required to accelerate weight (w) from 0 mph to 2 mph upwards.
the force required to accelerate weight (w) from 0 mph to 2 mph upwards
IS GREATER THAN
the force required to accelerate weight (w) from 0 mph to 2 mph horizontally.
this means
the force of weight (w) moving at 2 mph downward
IS GREATER THAN
the force of weight (w) moving at 2 mph horizontally.
Last edited by arthur on Thu Sep 13, 2007 2:17 am, edited 5 times in total.