[hamdani yusuf (OP)]

The statement that you quoted is from a user of stackexchange.com,

It's still wrong. Torque is a cause, not an effect.

It's not the error of Gemini.
Torque is caused by a force when the direction doesn't intersect with the axis of rotation.
The force itself is caused by something else.

The fact remains that torque is not "a force caused by rotation".

As explained by Meta AI,

The rotational version of force is torque.

Torque vs. Force
While force causes linear motion or acceleration, torque causes rotational motion or angular acceleration. Think of torque as a "twisting" or "turning" force that makes an object rotate around a pivot point or axis.

Key Aspects of Torque
1. Magnitude: The amount of rotational force applied.
2. Direction: The axis around which the rotation occurs.
3. Pivot point: The point around which the object rotates.

Torque is essential in understanding and designing rotational systems, such as engines, gears, and levers

[hamdani yusuf (OP)]

The wheels are still attached to my car. If I had used your definition of torque, they would have fallen off. And the parking brake works on a hill, despite your inability to calculate the pad force.

You seem to forget that I use the same definition as the English dictionary. You are the one using a different definition.

[hamdani yusuf (OP)]

You need to realise that I understand them better than you do.
Then you need to learn from what I told you about using a computer to get a more or less arbitrary  arbitrary  torque/ position function.

Then you need to think about it, and keep doing so until you see why it's possible to make a torque meter where a clockwise torque produces an anticlockwise rotation.

You might be genuinely thinking that way. But your posts so far don't seem to support your claim.
Let's compare facts and figures. How many control loops have you designed, implemented, commissioned, improved, tuned in the last twenty years?

How do you think the computer can sense the torque before it can calculate the appropriate response?

[hamdani yusuf (OP)]

Counterbalanced forces indicates equal and opposite forces while cancellation of force indicates it's removal- not the same thing at all. The girl on the scales maintains her downward force due to gravity, similarly a torque which fails to produce rotation is still a torque.

What do you call it in the case below? Cancel out or counterbalance?

...


Here's another example to show that expected rotational radius is not always the same as the real rotational radius.
It's similar to previous case, but this time a solid object is obstructing the rotation.
The question is, what's the torque produced by the force?

Since Paul has difficulty answering my simple question, can anyone help him out?

[hamdani yusuf (OP)]

The only one coming to wrong conclusions is YOU.

How to DESTROY Anyone in an Argument

Philosophers are often thought of as truth-seekers, but often people are more interested in the mucky world of simple debate, and there is a sardonic, sarcastic essay by Schopenhauer that can help us out here - "On the Art of Being Right". In here he compiles a series of tactics used (often highly dishonestly) to secure victory in an argument even when one is misinformed, or just downright wrong. And this is just what we will look at today, so that we can learn how to destroy anyone in an argument. And also, why we probably shouldn't


00:00 The Art of Being Right
01:32 "So What You're Saying Is..."
03:43 "What I'm Saying is..."
06:02 Endless Questions
09:09 Control the Metaphors
13:05 The "Strength" of Common Sense
15:36 Interru-
17:14 Make Your Opponent Angry
19:04 Toss a Word Salad
21:14 Miscellaneous Pointers
23:18 The Lessons of Deceit

Spoiler: show

To clarify - this video is sarcastic - these techniques are dishonest.

Which technique do you prefer the most?

[hamdani yusuf (OP)]

Torque (N.m) and energy (J) share the same SI unit,

Obviously not - ipsi dixit!. Torque is always stated in newtonmeters, and energy in joules. Dimensionally equivalent, but like length and circumference,  not the same thing,

You forget that rotational work equals torque times angular displacement.
Rotational power equals torque times angular velocity.

[hamdani yusuf (OP)]

This resolution was meant to solve identified problems in previous standard. But since the root cause of the problem hasn't been identified, the corrective action can't eliminate the problems and unintended side effects.

https://www.bipm.org/en/-/resolution-cgpm-20-8

Resolution 8 of the 20th CGPM (1995)

Elimination of the class of supplementary units in the SI

The 20th Conf?rence G?n?rale des Poids et Mesures,

considering

that the 11th Conf?rence G?n?rale in 1960 in its Resolution 12, establishing the Syst?me International d'Unit?s, SI, distinguished between three classes of SI units : the base units, the derived units, and the supplementary units, the last of these comprising the radian and the steradian,
that the status of the supplementary units in relation to the base units and the derived units gave rise to debate,
that the Comit? International des Poids et Mesures, in 1980, having observed that the ambiguous status of the supplementary units compromises the internal coherence of the SI, has in its Recommendation 1 (CI-1980) interpreted the supplementary units, in the SI, as dimensionless derived units,
approving the interpretation given by the Comit? International in 1980,

decides

to interpret the supplementary units in the SI, namely the radian and the steradian, as dimensionless derived units, the names and symbols of which may, but need not, be used in expressions for other SI derived units, as is convenient,
and, consequently, to eliminate the class of supplementary units as a separate class in the SI.
DOI : 10.59161/CGPM1995RES8E

A standard should aim for consistency. It should not depend on ad hoc convenience in case by case basis.

[paul cotter]

More diversion, there is no need to bring tensor analysis into the discussion of torque.

[alancalverd]

At least some of them must be correct because they are the same as current standard, which you claimed to be perfect.

A good apple is a good apple. A good orange is a good orange. Pretending that there is or ought to be a visible correspondence between apples and oranges is a bad idea, particularly if it leads you to develop meaningless oranges. Some of us realise from an early age that linear and rotational motion are very different.

You forget that rotational work equals torque times angular displacement.

How could I possibly forget the bloody obvious? And what gives you the ability to know what I forget?

[alancalverd]

The wheels are still attached to my car. If I had used your definition of torque, they would have fallen off. And the parking brake works on a hill, despite your inability to calculate the pad force.

You seem to forget that I use the same definition as the English dictionary. You are the one using a different definition.

Merriam-Webster:
a force that produces or tends to produce rotation or torsion

also : a measure of the effectiveness of such a force that consists of the product of the force and the perpendicular distance from the line of action of the force to the axis of rotation

Britannica: equal to the magnitude of the component of the force vector lying in the plane perpendicular to the axis, multiplied by the shortest distance between the axis and the direction of the force component.

No mention of angle, anywhere.

[paul cotter]

Hamdani, with respect to #903, I would need more information before I could give an answer. (1) The block half way along the spanner, is it touching the spanner or not? (2) Can we assume the top of the block is <<1metre? (3) If the block is not touching the spanner as the diagram shows, how stiff is the bolt?

[Bored chemist]

You need to realise that I understand them better than you do.
Then you need to learn from what I told you about using a computer to get a more or less arbitrary  arbitrary  torque/ position function.

Then you need to think about it, and keep doing so until you see why it's possible to make a torque meter where a clockwise torque produces an anticlockwise rotation.

You might be genuinely thinking that way. But your posts so far don't seem to support your claim.
Let's compare facts and figures. How many control loops have you designed, implemented, commissioned, improved, tuned in the last twenty years?

How do you think the computer can sense the torque before it can calculate the appropriate response?

Can I just check if you are actually mad?
You ask "How do you think the computer can sense the torque before it can calculate the appropriate response?"
I think that a better question is
How do you think the computer can calculate the appropriate response before it can sense the torque?

But never mind that, just get on with this.
... you need to think about it, and keep doing so until you see why it's possible to make a torque meter where a clockwise torque produces an anticlockwise rotation.

And re this "
Let's compare facts and figures. How many control loops have you designed, implemented, commissioned, improved, tuned in the last twenty years? "
For the sake of discussion (And to save the trouble  of estimating a count) , let's pretend it is just one. Let's say it's a system just like the one in the video about a sensitive balance

The point is that I understood that system and it seems you do not.

[Bored chemist]

And what gives you the ability to know what I forget?

Maybe this?

What he doesn't seem able to grasp is that we disagree because he is wrong.

Classic Dunning?Kruger effect

[Bored chemist]

As explained by Meta AI,

Why do you keep using AI?
Is it because you realise that you do not actually know what you are talking about?

[hamdani yusuf (OP)]

https://farside.ph.utexas.edu/teaching/301/lectures/node155.html

h = l/m
Clearly, h represents the angular momentum (per unit mass) of our planet around the Sun. Angular momentum is conserved (i.e., h is constant) because the force of gravitational attraction between the planet and the Sun exerts zero torque on the planet. (Recall, from Sect. 9, that torque is the rate of change of angular momentum.) The torque is zero because the gravitational force is radial in nature: i.e., its line of action passes through the Sun, and so its associated lever arm is of length zero.

We can't blame ancient people for not understanding the concept of rate of change, nor angular momentum. It's okay for them to try to define torque using simpler concepts which were easier to understand.

But now that most of us have already understood those concepts. Thus the modern definition of torque shouldn't be difficult to explain, at least to those with a decent scientific knowledge.

The reason for choosing a standard is to have a better consistency. Which is exactly what the proposed new standard units of rotational quantities have shown, compared to currently existing standard.

There are many equations relating torque to other physical quantities. But one of them is preferred by most people, especially in ancient times, to determine its standard unit, which is force times rotational radius. It's understandable  because they are relatively easier to measure, compared to other quantities like rotational inertia, angular momentum, angular velocity, angular acceleration, work, and power.

Moreover, the rotational radius can be considered constant in many situations. But that's not necessarily the case in orbital mechanics, as shown in the article above, where it generally changes over time. In a stable orbit where external forces are negligible, the angular momentum is conserved. Torque is the physical quantity which determines the rate of change of the angular momentum.

Some visualizations might help us understand the problem better.
https://en.wikipedia.org/wiki/Kepler%27s_laws_of_planetary_motion

Kepler's first law placing the Sun at one of the foci of an elliptical orbit


Heliocentric coordinate system (r, θ) for ellipse. Also shown are: semi-major axis a, semi-minor axis b and semi-latus rectum p; center of ellipse and its two foci marked by large dots. For θ = 0?, r = rmin and for θ = 180?, r = rmax.


The same (blue) area is swept out in a fixed time period. The green arrow is velocity. The purple arrow directed towards the Sun is the acceleration. The other two purple arrows are acceleration components parallel and perpendicular to the velocity.



Planet orbiting the Sun in a circular orbit (e=0.0)

Planet orbiting the Sun in an orbit with e=0.5
The red ray rotates at a constant angular velocity and with the same orbital time period as the planet, T=1.
S: Sun at the primary focus, C: Centre of ellipse, S': The secondary focus. In each case, the area of all sectors depicted is identical.

In this cases, net torque is zero because the force is directed toward the axis of rotation, which does not necessarily coincide with the geometrical center of the orbital trajectory. There is no change in angular momentum of the system. There is no change in total mechanical energy either (kinetic + potential).

Note that an ellipse has two foci which are geometrically identical. Only one of them is the center of planetary orbit. This can be seen as a more reason to distinguish between geometric radius and rotational radius, and reflect the difference in their respective units.

In rotational mechanics, the rotational radius is not generally constant. It's only constant for special cases. Although we were lucky that in many applications, it can be considered approximately constant to acceptable accuracy.

Consider this diagram to understand distinction between geometric and rotational radius.

Geometrically, there is no difference between Perihelion and Aphelion. But in rotational dynamics, they are a complete opposite.

[hamdani yusuf (OP)]

As explained by Meta AI,

Why do you keep using AI?
Is it because you realise that you do not actually know what you are talking about?

I'd like to remind especially younger members who haven't used AI, that we are at risk of being replaced by someone else who use AI effectively. If you think that you can compete with them without using AI, you are taking an unnecessary risk.

[hamdani yusuf (OP)]

Can I just check if you are actually mad?
You ask "How do you think the computer can sense the torque before it can calculate the appropriate response?"
I think that a better question is
How do you think the computer can calculate the appropriate response before it can sense the torque?

How is it? Do you type in the torque to the computer?

[hamdani yusuf (OP)]

Hamdani, with respect to #903, I would need more information before I could give an answer.
(1) The block half way along the spanner, is it touching the spanner or not?
(2) Can we assume the top of the block is <<1metre?
(3) If the block is not touching the spanner as the diagram shows, how stiff is the bolt?

1. You can see a small gap. Let's say it's 1 micron away.
2. You can approximate its height to 0.5 m.
3. Let's say if the obstructing block were removed, the bolt would turn by 1 microradian.

[hamdani yusuf (OP)]

And re this "
Let's compare facts and figures. How many control loops have you designed, implemented, commissioned, improved, tuned in the last twenty years? "
For the sake of discussion (And to save the trouble  of estimating a count) , let's pretend it is just one. Let's say it's a system just like the one in the video about a sensitive balance

The point is that I understood that system and it seems you do not.

You misunderstood that system. That's why you think someone else who disagree with you doesn't.

[hamdani yusuf (OP)]

No mention of angle, anywhere.

The angle is implied by the usage of rotational radius.