Saskatchewan has a centrifugal force?
Steam Turbine Failure South Africa
- Thread starter Shannow
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Originally Posted By: Shannow
Can't wait for your book to come out.
Do Astro and I get free copies ?
[censored] no! No soup for you!
Originally Posted By: Shannow
What I find funniest about your frame of reference ramblings, is that being a Man, thinking like a Man, and (I'm making an assumption here) presumably having the ability to drive a car like a Man.
Yes?
Originally Posted By: Shannow
In doing so, your subconscious will be constantly judging corner radii, entry speed, and steering input to balance the available centripetal forces with the acceleration required to follow your chosen course...you are working in the global frame of reference.
Not at all, actually. Truthfully, what I think about is the path I need to carve around a given corner so as to have the lowest degree/sec change in direction throughout the turn without managing to chomp on the granite curb on the outside of it.
Originally Posted By: Shannow
The amount of "force" crushing you against the door in your rotating frame of reference tells you nothing about the type of corner that you are in, how fast you are going, or what you need to do next to navigate safely to the end of the road...your subconscious knows it whether you acknowledge it or not.
Of course not. That's reactive stimuli. You need to be proactive behind the wheel. Engage turns on the outside and things like that. You need to look ahead to do that.
The various inertial forces and what I know I'm asking the car to do only tell me if the [censored] is about to slip out and I should let off the wheel a little.
Originally Posted By: Shannow
Your rotating frame of reference needs to be redefined for every single event/corner, rather than a global plane of reference where the same principals are at work every time.
Actually, my reference point is my own body and/or the car. As such, I view all inertial forces as external in origin. A way of simplifying the problem at hand.
I can't very well get out and tape measure my position relative to reference points on or near the road in good time, now can I?
And the car moves relative to the globe but the entire earth also moves relative to the car, moved by it. This goes right back to what I quoted other, way smarter and knowledgeable people saying about preferred and/or absolute reference frames.
My perception is just as accurate as an outside observer's.
Originally Posted By: Shannow
And for the last time, there IS NO FORCE crushing you against your seat...
Then, obviously, there must also be NO drag, lift or thrust. Those too are inertial forces. The inertia of atmospheric air and combustion gasses. I've pointed all this out already and the reasoning is full proof.
I do love, though, how you keep struggling against all odds of proving your premise and disproving my own.
Originally Posted By: Shannow
your body wants to either stay stationary, or at a constant direction and speed...UNLESS ACTED ON BY A FORCE...the force is centripetal force...your body is resisting change in direction, and it's the body of the car/seat that is transferring the force to get you to change direction (accelerate).
Define "still". What is your reference point/system? The world has moved on since Newton and people have realised it's best to use the problem at hand as the reference system rather than futilely seeking always for a universal, absolute, still or inertial reference system.
Physics is a tool like any other. And, like with many other tools, things start to go pear shaped when you make a goal out of the tool itself.
Originally Posted By: Astro14
Inertia, then is a property of physical law. Not a force.
Correct. Inertia is a property of mass. It is not a force. But it can exert force, relative to specific reference frames.
Remember the APDS round I gave as an example. Relative to the unfortunate target tank, the APDS shell exerts quite a good deal of force over a very short period.
Originally Posted By: Astro14
A force, by definition, causes and object to change direction or speed.
And therein lies the crux of the issue. Direction or speed in relation to what? What reference point or system?
In relation to the centre of rotation (which is a reference point, not a reference system), the hammer is at rest. It is the apparent centrifugal force that is a very real external force, as far as this system is concerned. Only thing preventing it from yanking the hammer away is the stronger centripetal force (equal to the centrifugal force up to the tensile strength of the hammer's wire or string, like traction is equal to torque until the limit of traction is reached).
Originally Posted By: Astro14
Motion is the change in position over time, or if using calculus, the first derivative of position with respect to time. Understand too that motion is a vector, it has both magnitude and direction. A change to either is the result of a force.
Again, position, speed, acceleration relative to what? There is no preferred or absolute reference frame. You must specify the reference frame.
Originally Posted By: Astro14
Here ends the first lesson in Physics.
Next time we convene I'll be expecting a complete summary of what you took away from it.
Originally Posted By: Astro14
So, from the first lesson, we now know that objects will stay in motion (same direction, same velocity) unless acted on.
We know you don't name your reference frame.
Originally Posted By: Astro14
Further, we know that Newton's Second Law states that F=MA (though in his seminal work; "Principia Mathematica", he never expresses it that way...that's the derivation). So, a change in an object's motion vector, an acceleration, can only be caused by a force. Acceleration is the the change in motion, or in calculus, the second derivative of postion with respect to time.
But no respect to a reference point/frame.
Originally Posted By: Astro14
How then, do we explain circular motion? The direction continues to change, so there must be a constant force that changes the direction. That force is the centripetal force. It changes the direction of the object TOWARDS THE CENTER OF THE CIRCLE.
You're only ever on the outside, looking in. From an encompassing reference frame to an encompassed one. You never bother to change perspective, to look from the inside out.
And even when only judging from outside, you should at least admit that inertia is capable of exerting force since it is clearly putting up resistance to centripetal acceleration (even so far as exceeding the tensile strength of the wire that is the upper limit to the centripetal force) and you admit the existence of other inertial forces, less conspicuous in their origin or nature (drag, lift, thrust, recoil).
Originally Posted By: Astro14
This is a key point of understanding. Without the force constantly applied to the center, the object would STOP going in a circle and proceed on a tangential vector. It's inertia, that physical property of all matter, would simply cause it to go straight. Newton's first law again.
Why do I care about whatever happens after the centrifugal force overcomes the tensile strength of the wire when I'm studying the system as it is before and up until failure?
Originally Posted By: Astro14
The only force is the centripetal force.
Yes, yes! This single force both tauts the hammer wire and breaks it as well.
Originally Posted By: Astro14
From Wikipeida (that internet-based font of knowledge, more authoritative than my copies of Physics textbooks...or my understanding of the subject):
I also quoted Britannica because I was sure you'd comment to that effect.
BTW, they even name centrifuges after this non-existent force. And centrifugal pumps too!
HAHA!
Originally Posted By: Astro14
So, circular motion is accelerated motion. It is accelerated towards the center of the circle.
Of course. I've said as much myself. That doesn't mean the centrifugal force, an inertial force, doesn't exist. Especially if you're going to claim other inertial forces do.
That would be a double standard for no apparent reason than that the other inertial forces have a more dissimulated nature and origin.
Originally Posted By: Astro14
Here ends the second lesson in physics.
Next time we convene I'll be expecting a complete summary of what you took away from it.
In closing, my erroneous human perception of the "non-existent" inertial forces is actually more accurate than your claims of absolute acceleration and non-acceleration. Because I always name the reference frame and you never do.
Can't wait for your book to come out.
Do Astro and I get free copies ?
[censored] no! No soup for you!
Originally Posted By: Shannow
What I find funniest about your frame of reference ramblings, is that being a Man, thinking like a Man, and (I'm making an assumption here) presumably having the ability to drive a car like a Man.
Yes?
Originally Posted By: Shannow
In doing so, your subconscious will be constantly judging corner radii, entry speed, and steering input to balance the available centripetal forces with the acceleration required to follow your chosen course...you are working in the global frame of reference.
Not at all, actually. Truthfully, what I think about is the path I need to carve around a given corner so as to have the lowest degree/sec change in direction throughout the turn without managing to chomp on the granite curb on the outside of it.
Originally Posted By: Shannow
The amount of "force" crushing you against the door in your rotating frame of reference tells you nothing about the type of corner that you are in, how fast you are going, or what you need to do next to navigate safely to the end of the road...your subconscious knows it whether you acknowledge it or not.
Of course not. That's reactive stimuli. You need to be proactive behind the wheel. Engage turns on the outside and things like that. You need to look ahead to do that.
The various inertial forces and what I know I'm asking the car to do only tell me if the [censored] is about to slip out and I should let off the wheel a little.
Originally Posted By: Shannow
Your rotating frame of reference needs to be redefined for every single event/corner, rather than a global plane of reference where the same principals are at work every time.
Actually, my reference point is my own body and/or the car. As such, I view all inertial forces as external in origin. A way of simplifying the problem at hand.
I can't very well get out and tape measure my position relative to reference points on or near the road in good time, now can I?
And the car moves relative to the globe but the entire earth also moves relative to the car, moved by it. This goes right back to what I quoted other, way smarter and knowledgeable people saying about preferred and/or absolute reference frames.
My perception is just as accurate as an outside observer's.
Originally Posted By: Shannow
And for the last time, there IS NO FORCE crushing you against your seat...
Then, obviously, there must also be NO drag, lift or thrust. Those too are inertial forces. The inertia of atmospheric air and combustion gasses. I've pointed all this out already and the reasoning is full proof.
I do love, though, how you keep struggling against all odds of proving your premise and disproving my own.
Originally Posted By: Shannow
your body wants to either stay stationary, or at a constant direction and speed...UNLESS ACTED ON BY A FORCE...the force is centripetal force...your body is resisting change in direction, and it's the body of the car/seat that is transferring the force to get you to change direction (accelerate).
Define "still". What is your reference point/system? The world has moved on since Newton and people have realised it's best to use the problem at hand as the reference system rather than futilely seeking always for a universal, absolute, still or inertial reference system.
Physics is a tool like any other. And, like with many other tools, things start to go pear shaped when you make a goal out of the tool itself.
Originally Posted By: Astro14
Inertia, then is a property of physical law. Not a force.
Correct. Inertia is a property of mass. It is not a force. But it can exert force, relative to specific reference frames.
Remember the APDS round I gave as an example. Relative to the unfortunate target tank, the APDS shell exerts quite a good deal of force over a very short period.
Originally Posted By: Astro14
A force, by definition, causes and object to change direction or speed.
And therein lies the crux of the issue. Direction or speed in relation to what? What reference point or system?
In relation to the centre of rotation (which is a reference point, not a reference system), the hammer is at rest. It is the apparent centrifugal force that is a very real external force, as far as this system is concerned. Only thing preventing it from yanking the hammer away is the stronger centripetal force (equal to the centrifugal force up to the tensile strength of the hammer's wire or string, like traction is equal to torque until the limit of traction is reached).
Originally Posted By: Astro14
Motion is the change in position over time, or if using calculus, the first derivative of position with respect to time. Understand too that motion is a vector, it has both magnitude and direction. A change to either is the result of a force.
Again, position, speed, acceleration relative to what? There is no preferred or absolute reference frame. You must specify the reference frame.
Originally Posted By: Astro14
Here ends the first lesson in Physics.
Next time we convene I'll be expecting a complete summary of what you took away from it.
Originally Posted By: Astro14
So, from the first lesson, we now know that objects will stay in motion (same direction, same velocity) unless acted on.
We know you don't name your reference frame.
Originally Posted By: Astro14
Further, we know that Newton's Second Law states that F=MA (though in his seminal work; "Principia Mathematica", he never expresses it that way...that's the derivation). So, a change in an object's motion vector, an acceleration, can only be caused by a force. Acceleration is the the change in motion, or in calculus, the second derivative of postion with respect to time.
But no respect to a reference point/frame.
Originally Posted By: Astro14
How then, do we explain circular motion? The direction continues to change, so there must be a constant force that changes the direction. That force is the centripetal force. It changes the direction of the object TOWARDS THE CENTER OF THE CIRCLE.
You're only ever on the outside, looking in. From an encompassing reference frame to an encompassed one. You never bother to change perspective, to look from the inside out.
And even when only judging from outside, you should at least admit that inertia is capable of exerting force since it is clearly putting up resistance to centripetal acceleration (even so far as exceeding the tensile strength of the wire that is the upper limit to the centripetal force) and you admit the existence of other inertial forces, less conspicuous in their origin or nature (drag, lift, thrust, recoil).
Originally Posted By: Astro14
This is a key point of understanding. Without the force constantly applied to the center, the object would STOP going in a circle and proceed on a tangential vector. It's inertia, that physical property of all matter, would simply cause it to go straight. Newton's first law again.
Why do I care about whatever happens after the centrifugal force overcomes the tensile strength of the wire when I'm studying the system as it is before and up until failure?
Originally Posted By: Astro14
The only force is the centripetal force.
Yes, yes! This single force both tauts the hammer wire and breaks it as well.
Originally Posted By: Astro14
From Wikipeida (that internet-based font of knowledge, more authoritative than my copies of Physics textbooks...or my understanding of the subject):
I also quoted Britannica because I was sure you'd comment to that effect.
BTW, they even name centrifuges after this non-existent force. And centrifugal pumps too!
HAHA!
Originally Posted By: Astro14
So, circular motion is accelerated motion. It is accelerated towards the center of the circle.
Of course. I've said as much myself. That doesn't mean the centrifugal force, an inertial force, doesn't exist. Especially if you're going to claim other inertial forces do.
That would be a double standard for no apparent reason than that the other inertial forces have a more dissimulated nature and origin.
Originally Posted By: Astro14
Here ends the second lesson in physics.
Next time we convene I'll be expecting a complete summary of what you took away from it.
In closing, my erroneous human perception of the "non-existent" inertial forces is actually more accurate than your claims of absolute acceleration and non-acceleration. Because I always name the reference frame and you never do.
maersk, I am glad that you feel that way and that your belief system works for you. I can see that I am wasting my time on your education, you have clearly missed the lessons because I did explain all of these things.
You keep your turtles.
I'll keep my physics.
You keep your turtles.
I'll keep my physics.
maersk it is abundantly clear at this point that while you know a lot of words, and think you know what they mean, you have no idea what you're talking about. You are abusing science here, and statements like "Physics is a tool like any other. And, like with many other tools, things start to go pear shaped when you make a goal out of the tool itself" show an unfortunately satisfaction in your own ignorance. It does however dovetail nicely with your apparent unwillingness to read up on the subject, or to just watch some old science TV shows. Afterall, if you dismiss the facts then you're free to create your own.
jeff
jeff
Ok, chief!
I win, I win, I win!
Originally Posted By: greenjp
maersk it is abundantly clear at this point that while you know a lot of words, and think you know what they mean, you have no idea what you're talking about. You are abusing science here, and statements like "Physics is a tool like any other. And, like with many other tools, things start to go pear shaped when you make a goal out of the tool itself" show an unfortunately satisfaction in your own ignorance. It does however dovetail nicely with your apparent unwillingness to read up on the subject, or to just watch some old science TV shows. Afterall, if you dismiss the facts then you're free to create your own.
jeff
How about you address at least some of my points before jumping to conclusions or resorting to ad hominem?
Thank you, bye!
I win, I win, I win!
Originally Posted By: greenjp
maersk it is abundantly clear at this point that while you know a lot of words, and think you know what they mean, you have no idea what you're talking about. You are abusing science here, and statements like "Physics is a tool like any other. And, like with many other tools, things start to go pear shaped when you make a goal out of the tool itself" show an unfortunately satisfaction in your own ignorance. It does however dovetail nicely with your apparent unwillingness to read up on the subject, or to just watch some old science TV shows. Afterall, if you dismiss the facts then you're free to create your own.
jeff
How about you address at least some of my points before jumping to conclusions or resorting to ad hominem?
Thank you, bye!
If by "win" you mean "frustrated people enough that the discussion ended", then yeah, you won.
By any other meaning, you lost.
Astro and Shannow did a fine job addressing your points, no need to repeat. I suggest reading up on fictitious forces and inertial vs. non-inertial reference frames. It will clarify your misunderstanding of these subjects.
jeff
By any other meaning, you lost.
Astro and Shannow did a fine job addressing your points, no need to repeat. I suggest reading up on fictitious forces and inertial vs. non-inertial reference frames. It will clarify your misunderstanding of these subjects.
jeff
Thanks Jeff...I was considering explaining how airplanes work too...but it's clear that Maersk was reading my words only to find points of disagreement, not to understand the principles involved. I addressed all of his points on forces and motion. I had yet to get to why physicists use approximations and constructs like "massless strings"...it's to teach the principles to those who still speak like children...
This wasn't a debate, where you "win" by maintaining your position - but Maersk doesn't understand that.
This wasn't a debate, where you "win" by maintaining your position - but Maersk doesn't understand that.
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Originally Posted By: greenjp
If by "win" you mean "frustrated people enough that the discussion ended", then yeah, you won.
By any other meaning, you lost.
If by losing you actually mean winning...
I lost, I lost, I lost!
Originally Posted By: greenjp
Astro and Shannow did a fine job addressing your points, no need to repeat. I suggest reading up on fictitious forces and inertial vs. non-inertial reference frames. It will clarify your misunderstanding of these subjects.
jeff
No, they didn't. They did not answer any of my many points satisfactorily.
They're stuck in the Newtonian view of the world. With universal, absolute reference frames and stuff like that. I keep trying to reach in and pull them out and they just club me over the head with Newton's crowbar.
If by "win" you mean "frustrated people enough that the discussion ended", then yeah, you won.
By any other meaning, you lost.
If by losing you actually mean winning...
I lost, I lost, I lost!
Originally Posted By: greenjp
Astro and Shannow did a fine job addressing your points, no need to repeat. I suggest reading up on fictitious forces and inertial vs. non-inertial reference frames. It will clarify your misunderstanding of these subjects.
jeff
No, they didn't. They did not answer any of my many points satisfactorily.
They're stuck in the Newtonian view of the world. With universal, absolute reference frames and stuff like that. I keep trying to reach in and pull them out and they just club me over the head with Newton's crowbar.
Quote:
They're stuck in the Newtonian view of the world. With universal, absolute reference frames and stuff like that.
What view of the world are you using?
They're stuck in the Newtonian view of the world. With universal, absolute reference frames and stuff like that.
What view of the world are you using?
I was trying to explain Newtonian mechanics and I did explain the reference frames and the relationship between frame and force. I answered the question as best you can in type. For the record, I don't have a Newtonian view of the world. My major course of study was Astrophysics, which is relativistic by nature. But before I was ready for that, I had to master the basics of Newtonian mechanics. For this discussion, I was attempting to explain the basics as a basis for further understanding.
Picasso had mastered the basics of painting early and the classical style by the time he was 12...then, he grew beyond it and invented several styles...but an artist can't simply pick up a brush and start out with cubism...he must master the basics first.
From the responses, including arguing with the steam turbine engineer and physicists, it was clear that maersk had the basics all confused.
Still does...
Picasso had mastered the basics of painting early and the classical style by the time he was 12...then, he grew beyond it and invented several styles...but an artist can't simply pick up a brush and start out with cubism...he must master the basics first.
From the responses, including arguing with the steam turbine engineer and physicists, it was clear that maersk had the basics all confused.
Still does...
Originally Posted By: maersk
No, they didn't. They did not answer any of my many points satisfactorily.
They're stuck in the Newtonian view of the world. With universal, absolute reference frames and stuff like that. I keep trying to reach in and pull them out and they just club me over the head with Newton's crowbar.
Sure they did, you just don't (or won't) understand it.
You seem to mistakenly think that you understand this stuff on some higher level, that by talking about non-inertial reference frames you're somehow more correct or something, I don't know.
use,
jeff
No, they didn't. They did not answer any of my many points satisfactorily.
They're stuck in the Newtonian view of the world. With universal, absolute reference frames and stuff like that. I keep trying to reach in and pull them out and they just club me over the head with Newton's crowbar.
Sure they did, you just don't (or won't) understand it.
You seem to mistakenly think that you understand this stuff on some higher level, that by talking about non-inertial reference frames you're somehow more correct or something, I don't know.
jeff
Originally Posted By: greenjp
Sure they did, you just don't (or won't) understand it.
Uh, no. They just went off on their own monologues. If people don't tackle my points of contention then it must mean they stand, no?
Originally Posted By: greenjp
You seem to mistakenly think that you understand this stuff on some higher level, that by talking about non-inertial reference frames you're somehow more correct or something, I don't know.
use,
jeff
No soup for you either, then.
Originally Posted By: Astro14
I was trying to explain Newtonian mechanics and I did explain the reference frames and the relationship between frame and force.
That's the problem right there. You went off on a multi tier lecture, like Shannow, instead of addressing the specific points I raised.
Sure they did, you just don't (or won't) understand it.
Uh, no. They just went off on their own monologues. If people don't tackle my points of contention then it must mean they stand, no?
Originally Posted By: greenjp
You seem to mistakenly think that you understand this stuff on some higher level, that by talking about non-inertial reference frames you're somehow more correct or something, I don't know.
jeff
No soup for you either, then.
Originally Posted By: Astro14
I was trying to explain Newtonian mechanics and I did explain the reference frames and the relationship between frame and force.
That's the problem right there. You went off on a multi tier lecture, like Shannow, instead of addressing the specific points I raised.
Originally Posted By: maersk
Originally Posted By: greenjp
Sure they did, you just don't (or won't) understand it.
Uh, no. They just went off on their own monologues. If people don't tackle my points of contention then it must mean they stand, no?
Originally Posted By: greenjp
You seem to mistakenly think that you understand this stuff on some higher level, that by talking about non-inertial reference frames you're somehow more correct or something, I don't know.
use,
jeff
No soup for you either, then.
Originally Posted By: Astro14
I was trying to explain Newtonian mechanics and I did explain the reference frames and the relationship between frame and force.
That's the problem right there. You went off on a multi tier lecture, like Shannow, instead of addressing the specific points I raised.
You think this is a debate that you "win"...it's not, it's science that is provable and complete in the context in which this discussion took place.
I addressed each of your points in turn. Each lesson was in response to a specific point you raised. But your points were based on flawed definitions of terms, inherently incompatible comparisons and flawed understanding. The only way to address that is comprehensively. You have yet to respond to all of my points. You have selectively chosen pieces of my presentation with which you disagree not realizing that it is a logical, inherently consistent and complete explanation. I took a lot of time to try and help you understand.
At this point, I can only say that you've won!
You're right...
It's turtles all the way down!
Originally Posted By: greenjp
Sure they did, you just don't (or won't) understand it.
Uh, no. They just went off on their own monologues. If people don't tackle my points of contention then it must mean they stand, no?
Originally Posted By: greenjp
You seem to mistakenly think that you understand this stuff on some higher level, that by talking about non-inertial reference frames you're somehow more correct or something, I don't know.
jeff
No soup for you either, then.
Originally Posted By: Astro14
I was trying to explain Newtonian mechanics and I did explain the reference frames and the relationship between frame and force.
That's the problem right there. You went off on a multi tier lecture, like Shannow, instead of addressing the specific points I raised.
You think this is a debate that you "win"...it's not, it's science that is provable and complete in the context in which this discussion took place.
I addressed each of your points in turn. Each lesson was in response to a specific point you raised. But your points were based on flawed definitions of terms, inherently incompatible comparisons and flawed understanding. The only way to address that is comprehensively. You have yet to respond to all of my points. You have selectively chosen pieces of my presentation with which you disagree not realizing that it is a logical, inherently consistent and complete explanation. I took a lot of time to try and help you understand.
At this point, I can only say that you've won!
You're right...
It's turtles all the way down!
Originally Posted By: maersk
That's the problem right there. You went off on a multi tier lecture, like Shannow, instead of addressing the specific points I raised.
You throw in a whole heap of unrelated strawmen, like drag, lift, gravity etc., and by our failure to cut every single one down, we are thereby ceding to your moving frames of reference.
Mate, you need a Copernican revelation...and I wouldn't light a smoke with all of that straw around.
BTW (true story), on my way to work yesterday, as I passed under a rail bridge, a Maersk container went over the bridge at exactly the same time as I passed under the bridge.
Impressive display of your winningness.
That's the problem right there. You went off on a multi tier lecture, like Shannow, instead of addressing the specific points I raised.
You throw in a whole heap of unrelated strawmen, like drag, lift, gravity etc., and by our failure to cut every single one down, we are thereby ceding to your moving frames of reference.
Mate, you need a Copernican revelation...and I wouldn't light a smoke with all of that straw around.
BTW (true story), on my way to work yesterday, as I passed under a rail bridge, a Maersk container went over the bridge at exactly the same time as I passed under the bridge.
Impressive display of your winningness.
Originally Posted By: Shannow
BTW (true story), on my way to work yesterday, as I passed under a rail bridge, a Maersk container went over the bridge at exactly the same time as I passed under the bridge.
Impressive display of your winningness.
I was really hoping he didn't start talking about ships - they use inertial navigation systems you know
jeff
BTW (true story), on my way to work yesterday, as I passed under a rail bridge, a Maersk container went over the bridge at exactly the same time as I passed under the bridge.
Impressive display of your winningness.
I was really hoping he didn't start talking about ships - they use inertial navigation systems you know
jeff
OK, one last appeal as to why a stationary plane of reference is advantageous over a rotating point (aside from the fact that it's the same plane of reference for every problem, and doesn't need to be re-defined every time).
Imagine a slow moving turbine, centripetal acceleration of 1 g, and a horizontal shaft...imagine you are doing a fatigue analysis of the blade attachment point.
From a stationary plane of reference, as the blade rotates, there is 1g+1g at BDC (2g), and 1g-1g (0g) at TDC...a constant gravitational force, and a rotating centripetal force.
Locate your frame of reference to the blade attachment point, and you have a constant "centrifugal force", and a cyclic gravitational force, rotating around you.
Honestly, which sounds more reasonable ?
Imagine a slow moving turbine, centripetal acceleration of 1 g, and a horizontal shaft...imagine you are doing a fatigue analysis of the blade attachment point.
From a stationary plane of reference, as the blade rotates, there is 1g+1g at BDC (2g), and 1g-1g (0g) at TDC...a constant gravitational force, and a rotating centripetal force.
Locate your frame of reference to the blade attachment point, and you have a constant "centrifugal force", and a cyclic gravitational force, rotating around you.
Honestly, which sounds more reasonable ?
Originally Posted By: greenjp
Originally Posted By: Shannow
BTW (true story), on my way to work yesterday, as I passed under a rail bridge, a Maersk container went over the bridge at exactly the same time as I passed under the bridge.
Impressive display of your winningness.
I was really hoping he didn't start talking about ships - they use inertial navigation systems you know
jeff
Inertial systems, which are largely laser interferometers these days...thank goodness we didn't start talking about Light, Electricity and Magnetism! I would hate to try and explain Quantum Mechanics or Maxwell's equations...
Originally Posted By: Shannow
BTW (true story), on my way to work yesterday, as I passed under a rail bridge, a Maersk container went over the bridge at exactly the same time as I passed under the bridge.
Impressive display of your winningness.
I was really hoping he didn't start talking about ships - they use inertial navigation systems you know
jeff
Inertial systems, which are largely laser interferometers these days...thank goodness we didn't start talking about Light, Electricity and Magnetism! I would hate to try and explain Quantum Mechanics or Maxwell's equations...
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Originally Posted By: Astro14
I addressed each of your points in turn. Each lesson was in response to a specific point you raised. But your points were based on flawed definitions of terms, inherently incompatible comparisons and flawed understanding. The only way to address that is comprehensively. You have yet to respond to all of my points. You have selectively chosen pieces of my presentation with which you disagree not realizing that it is a logical, inherently consistent and complete explanation. I took a lot of time to try and help you understand.
There you go off on a diatribe again.
No, you didn't. You claim you do it but never do.
Just a few examples:
How are drag, lift and thrust different from other inertial forces, whose existence you deny? The inertial of air molecules is exerting a measurable, incontrovertible force on the aircraft. Why do you consider some inertial forces real while others not?
Didn't even touch that one.
Why does the principle of equivalence not apply? Why aren't inertial forces every bit as real as gravity, for all intents or purposes? Or is gravity fake too? It suits me either way.
How can a single force acting on a given body break it up? How can a steel wire, suspended from a crane, snap without any weight dangling from it?
etc. etc. etc.
Originally Posted By: Astro14
At this point, I can only say that you've won!
You're right...
It's turtles all the way down!
Good, now relinquish the booty!
Originally Posted By: Shannow
You throw in a whole heap of unrelated strawmen, like drag, lift, gravity etc., and by our failure to cut every single one down, we are thereby ceding to your moving frames of reference.
There you go, you just admitted you're not addressing my points.
They are not strawmen. More like tin soldiers. I've given ample solid reasons for implicating those forces in the argument.
Originally Posted By: Shannow
Mate, you need a Copernican revelation...and I wouldn't light a smoke with all of that straw around.
Lead.
Originally Posted By: Shannow
BTW (true story), on my way to work yesterday, as I passed under a rail bridge, a Maersk container went over the bridge at exactly the same time as I passed under the bridge.
Impressive display of your winningness.
There you go. The hand of providence trying to nudge you a hint!
But do you listen?!
Originally Posted By: Shannow
Honestly, which sounds more reasonable ?
I could ask you the same thing about camera vs. world coordinates, for example. Or Euclidian vs. spherical geometry. Where would we be then?
Just because I prefer Euclidian geometry and I think the latter is counter intuitive and redundant doesn't mean I don't accept it.
I addressed each of your points in turn. Each lesson was in response to a specific point you raised. But your points were based on flawed definitions of terms, inherently incompatible comparisons and flawed understanding. The only way to address that is comprehensively. You have yet to respond to all of my points. You have selectively chosen pieces of my presentation with which you disagree not realizing that it is a logical, inherently consistent and complete explanation. I took a lot of time to try and help you understand.
There you go off on a diatribe again.
No, you didn't. You claim you do it but never do.
Just a few examples:
How are drag, lift and thrust different from other inertial forces, whose existence you deny? The inertial of air molecules is exerting a measurable, incontrovertible force on the aircraft. Why do you consider some inertial forces real while others not?
Didn't even touch that one.
Why does the principle of equivalence not apply? Why aren't inertial forces every bit as real as gravity, for all intents or purposes? Or is gravity fake too? It suits me either way.
How can a single force acting on a given body break it up? How can a steel wire, suspended from a crane, snap without any weight dangling from it?
etc. etc. etc.
Originally Posted By: Astro14
At this point, I can only say that you've won!
You're right...
It's turtles all the way down!
Good, now relinquish the booty!
Originally Posted By: Shannow
You throw in a whole heap of unrelated strawmen, like drag, lift, gravity etc., and by our failure to cut every single one down, we are thereby ceding to your moving frames of reference.
There you go, you just admitted you're not addressing my points.
They are not strawmen. More like tin soldiers. I've given ample solid reasons for implicating those forces in the argument.
Originally Posted By: Shannow
Mate, you need a Copernican revelation...and I wouldn't light a smoke with all of that straw around.
Lead.
Originally Posted By: Shannow
BTW (true story), on my way to work yesterday, as I passed under a rail bridge, a Maersk container went over the bridge at exactly the same time as I passed under the bridge.
Impressive display of your winningness.
There you go. The hand of providence trying to nudge you a hint!
But do you listen?!
Originally Posted By: Shannow
Honestly, which sounds more reasonable ?
I could ask you the same thing about camera vs. world coordinates, for example. Or Euclidian vs. spherical geometry. Where would we be then?
Just because I prefer Euclidian geometry and I think the latter is counter intuitive and redundant doesn't mean I don't accept it.
Originally Posted By: Astro14
Saskatchewan has a centrifugal force?
Yep, I can feel all -210 pounds of it right now. It's significantly larger than the centrifugal force in the U.S. The last time I was down there, it was only about -190 pounds.
Saskatchewan has a centrifugal force?
Yep, I can feel all -210 pounds of it right now. It's significantly larger than the centrifugal force in the U.S. The last time I was down there, it was only about -190 pounds.
I gave up reading around page 6. Now on page 10 this ridiculous argument is still going.
IMO, this is an argument about semantics and conventions. If ya'll all sat down with a big piece of paper, organized your thoughts, and started drawing forces- I think you'd come to an agreement soon enough.
Personally I think it's a little silly to say that "centrifugal force doesn't exist". That's a matter of semantics and convention. Shannow- you asked for a FBD. Picture this:
Imagine that tether-ball twirling around on a string. The only force you'll see on a FBD of that ball is centripetal force- I'll grant you that. But now consider a FBD of the point where the string attaches to the ball (we'll call it Point A). You have centripetal force (from the string) pulling Point A towards the axis of rotation. But you also have an equal and opposite force pulling Point A AWAY from the axis of rotation (from the ball).
Now this is a matter of semantics... but is it entirely unreasonable to call the force exerted by the ball onto Point A "centrifugal force"? That's exactly what your Average Joe would call it. And it's in the direction that your Average Joe would expect centrifugal force to be in. And it's a result of spinning an object around.
Looks like a duck. Walks like a duck. Quacks like a duck. You might say it's mis-named... but it certainly DOES exist.
IMO, this is an argument about semantics and conventions. If ya'll all sat down with a big piece of paper, organized your thoughts, and started drawing forces- I think you'd come to an agreement soon enough.
Personally I think it's a little silly to say that "centrifugal force doesn't exist". That's a matter of semantics and convention. Shannow- you asked for a FBD. Picture this:
Imagine that tether-ball twirling around on a string. The only force you'll see on a FBD of that ball is centripetal force- I'll grant you that. But now consider a FBD of the point where the string attaches to the ball (we'll call it Point A). You have centripetal force (from the string) pulling Point A towards the axis of rotation. But you also have an equal and opposite force pulling Point A AWAY from the axis of rotation (from the ball).
Now this is a matter of semantics... but is it entirely unreasonable to call the force exerted by the ball onto Point A "centrifugal force"? That's exactly what your Average Joe would call it. And it's in the direction that your Average Joe would expect centrifugal force to be in. And it's a result of spinning an object around.
Looks like a duck. Walks like a duck. Quacks like a duck. You might say it's mis-named... but it certainly DOES exist.
- Status
